Make more migrations reversible

db/migrate/20150406133311_add_invite_data_to_member.rb

 class AddInviteDataToMember < ActiveRecord::Migration
-  def change
+  def up
     add_column :members, :created_by_id, :integer
     add_column :members, :invite_email, :string
     add_column :members, :invite_token, :string
@@ -9,4 +9,15 @@ class AddInviteDataToMember < ActiveRecord::Migration
 
     add_index :members, :invite_token, unique: true
   end
+
+  def down
+    remove_index :members, :invite_token
+
+    change_column :members, :user_id, :integer, null: false
+
+    remove_column :members, :invite_accepted_at
+    remove_column :members, :invite_token
+    remove_column :members, :invite_email
+    remove_column :members, :created_by_id
+  end
 end

db/migrate/20150417122318_remove_import_data_from_project.rb

 class RemoveImportDataFromProject < ActiveRecord::Migration
-  def change
+  def up
     remove_column :projects, :import_data
   end
+
+  def down
+    add_column :projects, :import_data, :text
+  end
 end

db/migrate/20150425173433_add_default_snippet_visibility_to_app_settings.rb

 class AddDefaultSnippetVisibilityToAppSettings < ActiveRecord::Migration
-  def change
+  def up
     add_column :application_settings, :default_snippet_visibility, :integer
     visibility = Settings.gitlab.default_projects_features['visibility_level']
     execute("update application_settings set default_snippet_visibility = #{visibility}")
   end
+
+  def down
+    remove_column :application_settings, :default_snippet_visibility
+  end
 end