There is now support for the __stubs_only query parameter, prvoiding
mere stub representations of resources in a collection.
Merge remote-tracking branch 'origin/develop' into feature/stubs-only

Conflicts:
	src/ggrc/models/reflection.py
Merge pull request #212 from reciprocity/feature/stubs-only

Enable a stub representation of collections to reduce on the amount of data
Merge remote-tracking branch 'origin/develop' into feature/various-fixes