Merge branch 'project-file-tabs' into 'master'

Move project file links to tab bar.

The sidebar was getting awfully crowded, so I moved the file links to the tab bar alongside Activity and Readme. Unlike Readme, these files are not actually loaded in a tab, but simply link to the relevant blob, because we don't want to unnecessarily load the potentially large changelog or contribution guide on every project page load.

![Screen_Shot_2015-04-06_at_15.04.21](https://gitlab.com/gitlab-org/gitlab-ce/uploads/962e8073ab6dc8797f93ee754eb275ed/Screen_Shot_2015-04-06_at_15.04.21.png)

See merge request !497

CHANGELOG

@@ -20,7 +20,7 @@ v 7.10.0 (unreleased)
   - Omit the "email patches" link and fix plain diff view for merge commits
   - List new commits for newly pushed branch in activity view.
   - Add sidetiq gem dependency to match EE
-  - Add changelog, license and contribution guide links to project sidebar.
+  - Add changelog, license and contribution guide links to project tab bar.
   - Improve diff UI
   - Fix alignment of navbar toggle button (Cody Mize)
   - Fix checkbox rendering for nested task lists

app/views/projects/show.html.haml

@@ -4,15 +4,27 @@
 
 = render "home_panel"
 
-- readme = @repository.readme
 %ul.nav.nav-tabs
   %li.active
     = link_to '#tab-activity', 'data-toggle' => 'tab' do
       Activity
-  - if readme
+  - if @repository.readme
     %li
       = link_to '#tab-readme', 'data-toggle' => 'tab' do
         Readme
+  - if @repository.changelog
+    %li
+      = link_to changelog_url(@project) do
+        Changelog
+  - if @repository.contribution_guide
+    %li
+      = link_to contribution_guide_url(@project) do
+        Contribution guide
+  - if @repository.license
+    %li
+      = link_to license_url(@project) do
+        License
+
   .project-home-links
     - unless @project.empty_repo?
       = link_to pluralize(number_with_delimiter(@repository.commit_count), 'commit'), namespace_project_commits_path(@project.namespace, @project, @ref || @repository.root_ref)
@@ -56,17 +68,6 @@
                 Version:
                 %span.count
                   = @repository.blob_by_oid(version.id).data
-            - elsif @repository.changelog
-              = link_to changelog_url(@project), class: 'btn btn-block' do
-                View changelog
-
-            - if @repository.contribution_guide
-              = link_to contribution_guide_url(@project), class: 'btn btn-block' do
-                View contribution guide
-
-            - if @repository.license
-              = link_to license_url(@project), class: 'btn btn-block' do
-                View license
 
         .prepend-top-10.append-bottom-10
           %p
@@ -96,7 +97,7 @@
                 %span.light CI provided by
                 = link_to ci_service.title, ci_service.builds_path, :'data-no-turbolink' => 'data-no-turbolink'
 
-  - if readme
+  - if readme = @repository.readme
     .tab-pane#tab-readme
       %article.readme-holder#README
         = link_to namespace_project_blob_path(@project.namespace, @project, tree_join(@repository.root_ref, readme.name)) do