Use humanize instead of titleize for MR title suggestion

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

app/helpers/merge_requests_helper.rb

@@ -20,7 +20,7 @@ module MergeRequestsHelper
       target_project_id: target_project.id,
       source_branch: event.branch_name,
       target_branch: target_project.repository.root_ref,
-      title: event.branch_name.titleize
+      title: event.branch_name.humanize
     }
   end
 

app/views/projects/merge_requests/branch_from.js.haml

@@ -3,5 +3,5 @@
   var mrTitle = $('#merge_request_title');
 
   if(mrTitle.val().length == 0) {
-    mrTitle.val("#{params[:ref].titleize}");
+    mrTitle.val("#{params[:ref].humanize}");
   }