A user can currently follow a Collection, and another User.
Right now following doesn't do anything -- a subsequent commit will add
stream item support for followed Collections.
Also don't scope collection endpoints with /users/X or /groups/Y etc,
except for the index/create actions
test plan: use the api to follow and unfollow users and collections.
verify that you can follow something on a different shard, and it'll
still get returned correctly.
Change-Id: I9fd3f179885327e49f4d220784509de0ea23c0a7
Reviewed-on: https://gerrit.instructure.com/11057
Tested-by: Jenkins <jenkins@instructure.com>
Reviewed-by: Simon Williams <simon@instructure.com>
Brian Palmer