Group named "Members" causes conflict with group members page

[cnorris23]

If you create a group named "Members", you might end up with a URL like this ​http://example.com/groups/members/. If you go to the group members tab to view who the members are at ​http://example.com/members/members/ you will get a list of the members as expected. However, if you have a group named "Group 1" located at ​http://example.com/groups/group-1/, and then try to see the members of Group 1 at ​http://example.com/groups/group-1/members/, the content that is shown is that of ​http://example.com/groups/members/members/. The URL remains unchanged at ​http://example.com/groups/group-1/members/, and all of the action links (Home, Admin, Forum, Members, Send Invites) link to the correct group destination.

[apeatling]

(In [2557]) Fixes #1776