Possibility to create Milestones or Labels when Issues are disabled

app/controllers/projects/milestones_controller.rb

@@ -103,7 +103,9 @@ class Projects::MilestonesController < Projects::ApplicationController
   end
   def module_enabled
-    return render_404 unless @project.issues_enabled
+    unless @project.issues_enabled || @project.merge_requests_enabled
+      return render_404
+    end
   end
   def milestone_params

app/views/projects/issues/_head.html.haml → app/views/projects/_issues_nav.html.haml

 %ul.nav.nav-tabs
-  = nav_link(controller: :issues) do
-    = link_to project_issues_path(@project), class: "tab" do
-      Browse Issues
+  - if project_nav_tab? :issues
+    = nav_link(controller: :issues) do
+      = link_to project_issues_path(@project), class: "tab" do
+        Browse Issues
+  - if project_nav_tab? :merge_requests
+    = nav_link(controller: :merge_requests) do
+      = link_to project_merge_requests_path(@project), class: "tab" do
+        Merge Requests
   = nav_link(controller: :milestones) do
     = link_to 'Milestones', project_milestones_path(@project), class: "tab"
   = nav_link(controller: :labels) do
@@ -34,3 +39,14 @@
           = link_to new_project_issue_path(@project, issue: { assignee_id: params[:assignee_id], milestone_id: params[:milestone_id]}), class: "btn btn-new pull-left", title: "New Issue", id: "new_issue_link" do
             %i.fa.fa-plus
             New Issue
+
+  - if current_controller?(:merge_requests)
+    %li.pull-right
+      .pull-right
+        %button.btn.btn-default.sidebar-expand-button
+          %i.icon.fa.fa-list
+            
+        - if can? current_user, :write_merge_request, @project
+          = link_to new_project_merge_request_path(@project), class: "pull-right btn btn-new", title: "New Merge Request" do
+            %i.fa.fa-plus
+            New Merge Request

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

-= render "head"
+= render "projects/issues_nav"
 .row
   .fixed.fixed.sidebar-expand-button.hidden-lg.hidden-md.hidden-xs
     %i.fa.fa-list.fa-2x

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

-= render "projects/issues/head"
+= render "projects/issues_nav"
 - if can? current_user, :admin_label, @project
   = link_to new_project_label_path(@project), class: "pull-right btn btn-new" do

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

-- if can? current_user, :write_merge_request, @project
-  = link_to new_project_merge_request_path(@project), class: "pull-right btn btn-new", title: "New Merge Request" do
-    %i.fa.fa-plus
-    New Merge Request
-%h3.page-title
-  Merge Requests
-%hr
+= render "projects/issues_nav"
+
 .row
   .fixed.sidebar-expand-button.hidden-lg.hidden-md
     %i.fa.fa-list.fa-2x

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

-= render "projects/issues/head"
+= render "projects/issues_nav"
 .milestones_content
   %h3.page-title
     Milestones

app/views/projects/milestones/show.html.haml

-= render "projects/issues/head"
+= render "projects/issues_nav"
 %h3.page-title
   Milestone ##{@milestone.iid}
   .pull-right