Generate labels set from issues page

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

app/controllers/projects/labels_controller.rb

@@ -13,7 +13,7 @@ class Projects::LabelsController < Projects::ApplicationController
   def generate
     Gitlab::IssuesLabels.generate(@project)
 
-    redirect_to project_labels_path(@project)
+    redirect_to project_issues_path(@project)
   end
 
   protected

app/views/shared/_project_filter.html.haml

@@ -40,6 +40,12 @@
                   .pull-right
                     %i.icon-remove
 
+          - if issue_label_names.empty?
+            .light-well
+              Add first label to your issues
+              %br
+              or #{link_to 'generate', generate_project_labels_path(@project), method: :post} default set of labels
+
     %fieldset
       - if %w(state scope milestone_id assignee_id label_name).select { |k| params[k].present? }.any?
         = link_to project_entities_path, class: 'cgray pull-right' do