404 when you try to create a new group-milestone
Summary
When you try to create a new milestone for a group, you get a 404 on https://gitlab.com/GROUPNAME/milestones/new
Steps to reproduce
Try to open https://gitlab.com/GROUPNAME/milestones/new with a group, in which you are allowed to create milestones.
Expected behavior
The UI to create a new milestone across several projects of one group should appear.
Actual behavior
Response with 404.
Personal note
Thanks for all the great work! It's a pleasure to use gitlab!