Allow the configuration of image_member_quota
in Glance API. This error blocks the ability
of sharing images if the default value (128)
is reached.
Closes-bug: 1724879
Depends-on: Idc72c85943baf3d720500d2c30a813663f2927da
Change-Id: I6a3d4d9666378bbc5610d96bcedc81cf4c5d7de7