Fix admin nav active state

app/views/layouts/ci/_nav_admin.html.haml

 %ul.nav.nav-pills.nav-stacked.admin-menu
-  = nav_link path: 'projects' do
+  = nav_link path: 'projects#index' do
     = link_to ci_admin_projects_path do
       %i.fa.fa-list-alt
       Projects
-  = nav_link path: 'events' do
+  = nav_link path: 'events#index' do
     = link_to ci_admin_events_path do
       %i.fa.fa-book
       Events
@@ -13,7 +13,7 @@
       Runners
       %small.pull-right
         = Ci::Runner.count(:all)
-  = nav_link path: 'builds' do
+  = nav_link path: 'builds#index' do
     = link_to ci_admin_builds_path do
       %i.fa.fa-link
       Builds