Merge branch 'new-tag-branch-authorization' into 'master'

Add authorization to new branch/tag pages.

The create actions have authorization, the new actions didn't,
so no-one unauthorized could actually do anything, but it was wrong(TM).

See merge request !1979

app/controllers/projects/branches_controller.rb

@@ -3,7 +3,7 @@ class Projects::BranchesController < Projects::ApplicationController
   # Authorize
   before_action :require_non_empty_project
   before_action :authorize_download_code!
-  before_action :authorize_push_code!, only: [:create, :destroy]
+  before_action :authorize_push_code!, only: [:new, :create, :destroy]
 
   def index
     @sort = params[:sort] || 'name'

app/controllers/projects/tags_controller.rb

@@ -2,7 +2,7 @@ class Projects::TagsController < Projects::ApplicationController
   # Authorize
   before_action :require_non_empty_project
   before_action :authorize_download_code!
-  before_action :authorize_push_code!, only: [:create]
+  before_action :authorize_push_code!, only: [:new, :create]
   before_action :authorize_admin_project!, only: [:destroy]
 
   def index