Add driver and resource caching using redis.

* Add service.cache module.
* Remove references to rtwo implementation details in core model
  helper methods.
* Update versions in requirements.

	modified:   core/models/instance.py
	modified:   core/models/size.py
	modified:   requirements.txt
	new file:   service/cache.py
Remove auth for celery's flower.
	modified:   extras/init.d/celeryd.default
Use service.cache in api.instance.

	modified:   api/instance.py
Add VolumeStatusHistory to Volume.

* Add VolumeStatusHistory.
* Add VolumeStatus.
* Update Volume to use VolumeStatusHistory.

	new file:   core/migrations/0060_auto__add_volumestatus.py
	new file:   core/migrations/0061_auto__add_volumestatushistory.py
	modified:   core/models/volume.py
Use service.cache module.
	modified:   service/allocation.py
	modified:   service/quota.py
	modified:   service/tasks/allocation.py
PEP8 Compliance.
	modified:   api/project.py
Use the same atmosphere instance token through the entire deploy.
	modified:   service/deploy.py
	modified:   service/instance.py
	modified:   service/task.py
	modified:   service/tasks/driver.py
Merge branch 'abyssinian-nightjar' of github.com:iPlantCollaborativeOpenSource/atmosphere into abyssinian-nightjar

Conflicts:
	api/project.py
	core/models/volume.py
	extras/init.d/celeryd.default.dist