Add fade out to left side of layout nav; remove dropdown nav helper; remove controls button from mobile

Add new HA diagrams [ci skip]

## What does this MR do?

Adds new HA diagrams created by @lukebabb (Thanks @lukebabb!)

See merge request !4289

Fix RuboCop

See merge request !4294

New confirmation email

See merge request !3354

[ci skip]

This makes it easier to debug style rules.

Remove `issue_to_atom` helper



See merge request !4265

Improve design of Pipeline view

## What does this MR do?

Improves current design of Pipelines view when there is multiple stages.
This makes the statuses clickable and makes the view more compact.

## Screenshots (if relevant)

![Screen_Shot_2016-05-21_at_01.20.40](/uploads/dd031b7af7005c7a61f3165fefa8b7c9/Screen_Shot_2016-05-21_at_01.20.40.png)

cc @DouweM @markpundsack @rspeicher @marin 

See merge request !4230

Remove `event_to_atom` helper



See merge request !4234

Fix for import URL URI problem when URL contains a space

Fixes https://gitlab.com/gitlab-org/gitlab-ce/issues/17559

Prevents an already encoded URL to be encoded again - preventing %20 => %25%20

See merge request !4180

Fix forks creation when visibility level is restricted

fixes #10725

See merge request !4283

Updated error message when project limit is zero

When the project limit is zero & the user tries to create a project, the
error displayed is now 'Personal project creation is not allowed. Please
contact your administrator with questions'

Closes #17691

See merge request !4280

Related merge request text alignment

Fixed the alignment of the text 'When this merge request is accepted...' on issues page

![Screen_Shot_2016-05-23_at_14.59.48](/uploads/5d2f4be94108364a9d004169a6825a9e/Screen_Shot_2016-05-23_at_14.59.48.png)

See merge request !4251

[ci skip]

Write some thoughts to the UI guide

cc @skyruler 

See merge request !4290

Issuable filtering improvements

This improves the filtering of issues and merge requests by creating a single file that encapsulates all the filtering. Previously this was done with a file for issues and a file for merge requests.

Created the ability for the text search to be done alongside other filterables. Previously because this was outside the filterable form, this wasn't possible and would instead do either filter dropdown or text filter - not both. Fixes #4252 

Fixed issue with not being able to filter and sort issues without refreshing the page. Fixes #15269 

See merge request !3699

Enable multiple compatible Rubocop cops

## What does this MR do?

This MR enables multiple Rubocop cops, that are already compatible with
our codebase. See #17406.

Cops enabled:

```text
Style/ArrayJoin:
  Description: Use Array#join instead of Array#*.
  StyleGuide: https://github.com/bbatsov/ruby-style-guide#array-join
----------------
Style/Attr:
  Description: Checks for uses of Module#attr.
  StyleGuide: https://github.com/bbatsov/ruby-style-guide#attr
----------------
Style/BlockComments:
  Description: Do not use block comments.
  StyleGuide: https://github.com/bbatsov/ruby-style-guide#no-block-comments
----------------
Style/ClassMethods:
  Description: Use self when defining module/class methods.
  StyleGuide: https://github.com/bbatsov/ruby-style-guide#def-self-class-methods
----------------
Style/EndBlock:
  Description: Avoid the use of END blocks.
  StyleGuide: https://github.com/bbatsov/ruby-style-guide#no-END-blocks
----------------
Style/EvenOdd:
  Description: Favor the use of Fixnum#even? && Fixnum#odd?
  StyleGuide: https://github.com/bbatsov/ruby-style-guide#predicate-methods
----------------
Style/FileName:
  Description: Use snake_case for source file names.
  StyleGuide: https://github.com/bbatsov/ruby-style-guide#snake-case-files
  ExpectMatchingDefinition: false
----------------
Style/FirstMethodParameterLineBreak:
  Description: Checks for a line break before the first parameter in a multi-line method
    parameter definition.
----------------
Style/FlipFlop:
  Description: Checks for flip flops
  StyleGuide: https://github.com/bbatsov/ruby-style-guide#no-flip-flops
----------------
Style/GlobalVars:
  Description: Do not introduce global variables.
  StyleGuide: https://github.com/bbatsov/ruby-style-guide#instance-vars
  Reference: http://www.zenspider.com/Languages/Ruby/QuickRef.html
----------------
Style/IfWithSemicolon:
  Description: Do not use if x; .... Use the ternary operator instead.
  StyleGuide: https://github.com/bbatsov/ruby-style-guide#no-semicolon-ifs
----------------
Style/LambdaCall:
  Description: Use lambda.call(...) instead of lambda.(...).
  StyleGuide: https://github.com/bbatsov/ruby-style-guide#proc-call
  EnforcedStyle: call
----------------
Style/MethodName:
  Description: Use the configured style when naming methods.
  StyleGuide: https://github.com/bbatsov/ruby-style-guide#snake-case-symbols-methods-vars
  EnforcedStyle: snake_case
----------------
Style/MultilineMethodDefinitionBraceLayout:
  Description: Checks that the closing brace in a method definition is symmetrical with
    respect to the opening brace and the method parameters.
----------------
Style/NestedModifier:
  Description: Avoid using nested modifiers.
  StyleGuide: https://github.com/bbatsov/ruby-style-guide#no-nested-modifiers
----------------
Style/OpMethod:
  Description: When defining binary operators, name the argument other.
  StyleGuide: https://github.com/bbatsov/ruby-style-guide#other-arg
----------------
Style/SignalException:
  Description: Checks for proper usage of fail and raise.
  StyleGuide: https://github.com/bbatsov/ruby-style-guide#prefer-raise-over-fail
  EnforcedStyle: only_raise
----------------
Style/SpaceAfterNot:
  Description: Tracks redundant space after the ! operator.
  StyleGuide: https://github.com/bbatsov/ruby-style-guide#no-space-bang
----------------
Style/SpaceBeforeSemicolon:
  Description: No spaces before semicolons.
----------------
Style/SpaceInsideRangeLiteral:
  Description: No spaces inside range literals.
  StyleGuide: https://github.com/bbatsov/ruby-style-guide#no-space-inside-range-literals
----------------
Style/SpaceInsideStringInterpolation:
  Description: Checks for padding/surrounding spaces inside string interpolation.
  StyleGuide: https://github.com/bbatsov/ruby-style-guide#string-interpolation
  EnforcedStyle: no_space
----------------
Style/StabbyLambdaParentheses:
  Description: Check for the usage of parentheses around stabby lambda arguments.
  StyleGuide: https://github.com/bbatsov/ruby-style-guide#stabby-lambda-with-args
  EnforcedStyle: require_parentheses
----------------
Style/StringMethods:
  Description: Checks if configured preferred methods are used over non-preferred.
  PreferredMethods:
    intern: to_sym
----------------
Style/VariableInterpolation:
  Description: Don't interpolate global, instance and class variables directly in strings.
  StyleGuide: https://github.com/bbatsov/ruby-style-guide#curlies-interpolate
----------------
Style/VariableName:
  Description: Use the configured style when naming variables.
  StyleGuide: https://github.com/bbatsov/ruby-style-guide#snake-case-symbols-methods-vars
  EnforcedStyle: snake_case
----------------
Style/WhenThen:
  Description: Use when x then ... for one-line cases.
  StyleGuide: https://github.com/bbatsov/ruby-style-guide#one-line-cases
----------------
Style/WhileUntilModifier:
  Description: Favor modifier while/until usage when you have a single-line body.
  StyleGuide: https://github.com/bbatsov/ruby-style-guide#while-as-a-modifier
  MaxLineLength: 80
```

Closes #17406 

See merge request !4286

Fixed issue with GitLab import buttons having a spinner

![import](/uploads/db635f1d62affefca027d5fd4f545cd1/import.gif)

Closes #17232

See merge request !4276

Add a gitlab:db:configure rake task to handle conditionally seeding or
migrating the database.

Fixes: https://gitlab.com/gitlab-org/gitlab-ce/issues/17328

See merge request !4062

Move tags to column in generic_commit_status

Part of https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/4249    

cc @ayufan 



See merge request !4277

[ci skip]

Fix grammar and wording in text on various pages.

## What does this MR do?

Fixes various grammatical and/or wording issues I found while copyediting on the plane :)

## Why was this MR needed?

Incorrect grammar and weird/confusing wording makes the product look less polished and professional.

See merge request !4237

Fix typo in HA documentation

[ci skip]

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Increased zindex of layout nav

This fixes issues where group inputs would be above the dropdown in the nav

![Screen_Shot_2016-05-17_at_10.14.18](/uploads/08e4a43922051c28377ae6f34725ccc6/Screen_Shot_2016-05-17_at_10.14.18.png)

Closes #17524

See merge request !4176

Switch the gitlab:db:configure task to use tables.any? instead of looking specifically for the schema_migrations table