Auth Composite Changes for ObjectStorage

* Removed the ObjectStorageAuthComposite class
  from the ObjectStorage fixture.
* Changed all calls in the fixture to use the
  new ObjectStorageComposite class
* Changed all calls in the generators to use
  the new ObjectStorageComposite
* Fixed PEP8 issues in generators

Change-Id: I0bb05434c6c46f419c339744fea100e6cf04dedf