Protected branches system (#339)

* Protected branches system

* Moved default branch to branches section (`:org/:reponame/settings/branches`).
* Initial support Protected Branch.
  - Admin does not restrict
  - Owner not to limit
  - To write permission restrictions

* reformat tmpl

* finished the UI and add/delete protected branch response

* remove unused comment

* indent all the template files and remove ru translations since we use crowdin

* fix the push bug

cmd/web.go

@@ -421,6 +421,11 @@ func runWeb(ctx *cli.Context) error {
 				m.Post("/access_mode", repo.ChangeCollaborationAccessMode)
 				m.Post("/delete", repo.DeleteCollaboration)
 			})
+			m.Group("/branches", func() {
+				m.Combo("").Get(repo.ProtectedBranch).Post(repo.ProtectedBranchPost)
+				m.Post("/can_push", repo.ChangeProtectedBranch)
+				m.Post("/delete", repo.DeleteProtectedBranch)
+			})
 
 			m.Group("/hooks", func() {
 				m.Get("", repo.Webhooks)