In manage user groups, filter by user or address

[oliverheywood451]

As an admin user I might like to filter the list of usergroups to show all the groups a specific user belongs to. Or I might want to show all the groups a specific address is assigned to.

There should be a multi-select with two options - user or address. There should be a text input with a dropdown of type ahead suggestions searching either addresses or users. When a user or address is selected, filter the user group list to only show groups with assignments to that object.