add screenshots to gitlab-flow article

doc/workflow/gitlab_flow.md

@@ -95,7 +95,7 @@ In this flow it is not common to have a production branch (or git flow master br
 
 # Merge/pull requests with GitLab flow
 
-![Merge request with line comments]() Merge or pull requests are created in a git management application and ask an assigned person to merge two branches.
+![Merge request with line comments](mr_inline_comments.png) Merge or pull requests are created in a git management application and ask an assigned person to merge two branches.
 Tools such as GitHub and Bitbucket choose the name pull request since the first manual action would be to pull the feature branch.
 Tools such as GitLab and Gitorious choose the name merge request since that is the final action that is requested of the assignee.
 In this article we'll refer to them as merge requests.
@@ -118,7 +118,7 @@ So if you want to merge it into a protected branch you assign it to someone with
 
 # Issues with GitLab flow
 
-![Merge request with the branch name 15-require-a-password-to-change-it and assignee field shown]() GitLab flow is a way to make the relation between the code and the issue tracker more transparent.
+![Merge request with the branch name 15-require-a-password-to-change-it and assignee field shown](merge_request.png) GitLab flow is a way to make the relation between the code and the issue tracker more transparent.
 
 Any significant change to the code should start with an issue where the goal is described.
 Having a reason for every code change is important to inform everyone on the team and to help people keep the scope of a feature branch small.
@@ -150,7 +150,7 @@ It is possible that one feature branch solves more than one issue.
 
 # Linking and closing issues from merge requests
 
-![Merge request showing the linked issues that will be closed]() Linking to the issue can happen by mentioning them from commit messages (fixes #14, closes #67, etc.) or from the merge request description.
+![Merge request showing the linked issues that will be closed](close_issue_mr.png) Linking to the issue can happen by mentioning them from commit messages (fixes #14, closes #67, etc.) or from the merge request description.
 In GitLab this creates a comment in the issue that the merge requests mentions the issue.
 And the merge request shows the linked issues.
 These issues are closed once code is merged into the default branch.
@@ -161,7 +161,7 @@ If you have an issue that spans across multiple repositories, the best thing is
 
 # Squashing commits with rebase
 
-![Vim screen showing the rebase view]() With git you can use an interactive rebase (rebase -i) to squash multiple commits into one and reorder them.
+![Vim screen showing the rebase view](rebase.png) With git you can use an interactive rebase (rebase -i) to squash multiple commits into one and reorder them.
 This functionality is useful if you made a couple of commits for small changes during development and want to replace them with a single commit or if you want to make the order more logical.
 However you should never rebase commits you have pushed to a remote server.
 Somebody can have referred to the commits or cherry-picked them.
@@ -185,7 +185,7 @@ Git management software will always create a merge commit when you accept a merg
 
 # Do not order commits with rebase
 
-![List of sequencial merge commits]() With git you can also rebase your feature branch commits to order them after the commits on the master branch.
+![List of sequential merge commits](merge_commits.png) With git you can also rebase your feature branch commits to order them after the commits on the master branch.
 This prevents creating a merge commit when merging master into your feature branch and creates a nice linear history.
 However, just like with squashing you should never rebase commits you have pushed to a remote server.
 This makes it impossible to rebase work in progress that you already shared with your team which is something we recommend.
@@ -220,13 +220,13 @@ If you rebase code the history is incorrect, and there is no way for tools to re
 
 # Voting on merge requests
 
-![Voting slider in GitLab]() It is common to voice approval or disapproval by using +1 or -1 emoticons.
+![Voting slider in GitLab](voting_slider.png) It is common to voice approval or disapproval by using +1 or -1 emoticons.
 In GitLab the +1 and -1 are aggregated and shown at the top of the merge request.
 As a rule of thumb anything that doesn't have two times more +1's than -1's is suspect and should not be merged yet.
 
 # Pushing and removing branches
 
-![Remove checkbox for branch in merge requests]() We recommend that people push their feature branches frequently, even when they are not ready for review yet.
+![Remove checkbox for branch in merge requests](remove_checkbox.png) We recommend that people push their feature branches frequently, even when they are not ready for review yet.
 By doing this you prevent team members from accidentally starting to work on the same issue.
 Of course this situation should already be prevented by assigning someone to the issue in the issue tracking software.
 However sometimes one of the two parties forgets to assign someone in the issue tracking software.
@@ -238,7 +238,7 @@ When you reopen an issue you need to create a new merge request.
 
 # Committing often and with the right message
 
-![Good and bad commit message]() We recommend to commit early and often.
+![Good and bad commit message](good_commit.png) We recommend to commit early and often.
 Each time you have a functioning set of tests and code a commit can be made.
 The advantage is that when an extension or refactor goes wrong it is easy to revert to a working version.
 This is quite a change for programmers that used SVN before, they used to commit when their work was ready to share.
@@ -252,7 +252,7 @@ To see more information about the formatting of commit messages please see this
 
 # Testing before merging
 
-![Merge requests showing the test states, red, yellow and green]() In old workflows the Continuous Integration (CI) server commonly ran tests on the master branch only.
+![Merge requests showing the test states, red, yellow and green](ci_mr.png) In old workflows the Continuous Integration (CI) server commonly ran tests on the master branch only.
 Developers had to ensure their code did not break the master branch.
 When using GitLab flow developers create their branches from this master branch so it is essential it is green.
 Therefore each merge request must be tested before it is accepted.
@@ -267,7 +267,7 @@ If you have long lived feature branches that last for more than a few days you s
 
 # Merging in other code
 
-![Shell output showing git pull output]() When initiating a feature branch, always start with an up to date master to branch off from.
+![Shell output showing git pull output](git_pull.png) When initiating a feature branch, always start with an up to date master to branch off from.
 If you know beforehand that your work absolutely depends on another branch you can also branch from there.
 If you need to merge in another branch after starting explain the reason in the merge commit.
 If you have not pushed your commits to a shared location yet you can also rebase on master or another feature branch.