Merge branch 'dz-one-ci-cd-tab' into 'master'

Merge Builds and Pipelines tab into one

Based on https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/4053#note_12064642. Main idea is to keep all CI-related pages under one tab. So we can keep top navigation clean. 

First I tried `CI/CD` naming but it looked weird so I just used Pipelines as tab name. I did not change project settings naming. 

cc @ayufan @markpundsack @jschatz1 

See merge request !4340

app/views/layouts/nav/_project.html.haml

@@ -52,15 +52,6 @@
           = icon('ship fw')
           %span
             Pipelines
-            %span.badge.count.ci_counter= number_with_delimiter(@project.ci_commits.running_or_pending.count)
-
-    - if project_nav_tab? :builds
-      = nav_link(controller: %w(builds)) do
-        = link_to project_builds_path(@project), title: 'Builds', class: 'shortcuts-builds' do
-          = icon('cubes fw')
-          %span
-            Builds
-            %span.badge.count.builds_counter= number_with_delimiter(@project.builds.running_or_pending.count(:all))
 
     - if project_nav_tab? :container_registry
       = nav_link(controller: %w(container_registry)) do
@@ -132,4 +123,10 @@
       = link_to new_namespace_project_issue_path(@project.namespace, @project), class: 'shortcuts-new-issue' do
         Create a new issue
 
+    -# Shortcut to builds page
+    - if project_nav_tab? :builds
+      %li.hidden
+        = link_to project_builds_path(@project), title: 'Builds', class: 'shortcuts-builds' do
+          Builds
+
     .fade-right

app/views/projects/builds/index.html.haml

 - page_title "Builds"
+= render "projects/pipelines/head"
 
 .top-area
   %ul.nav-links

app/views/projects/pipelines/_head.html.haml

+%ul.nav-links
+  - if project_nav_tab? :pipelines
+    = nav_link(controller: :pipelines) do
+      = link_to project_pipelines_path(@project), title: 'Pipelines', class: 'shortcuts-pipelines' do
+        %span
+          Pipelines
+          %span.badge.count.ci_counter= number_with_delimiter(@project.ci_commits.running_or_pending.count)
+
+  - if project_nav_tab? :builds
+    = nav_link(controller: %w(builds)) do
+      = link_to project_builds_path(@project), title: 'Builds', class: 'shortcuts-builds' do
+        %span
+          Builds
+          %span.badge.count.builds_counter= number_with_delimiter(@project.builds.running_or_pending.count(:all))

app/views/projects/pipelines/index.html.haml

 - page_title "Pipelines"
+= render "projects/pipelines/head"
 
 .top-area
   %ul.nav-links