Controller and Operation introduced
Exceptions reorganized and Controller exceptions added.
Controller prototype improved
Content negotiation added
Merge branch 'prefix-import' into collection-operation

Conflicts:
	oldman/management/manager.py
	tests/default_model.py
CRUD test updated
CRUD.get now return the content-type
Merge branch 'master' into operation-controller

Conflicts:
	requirements.txt
Fix some bad automatic comment updates
Merge branch 'operation-controller'