really dirty and NOT TO BE USED caching

just proof of concept of performance gains
more advanced caching

cache views with doc_ids
example implementations to test easy wins (to be changed)
new pillow that does background invalidation of users, domains and groups
reports and manage data tabs cached mostly

still need to find a right wrapping for caching...but instructive
for performance boosts
updiantg additiona cache calls
updating documentation
Merge branch 'master' into smarterer_caching
cache calls cleaned up and adding wrapper kwarg.
cache invalidation pillow

adding logging for seeing how bad cache invalidation would get once things get big.
adding cache invalidation pillow to pillowtops
few more cached_views
Merge branch 'smarterer_caching' into staging2

Conflicts:
	corehq/apps/reports/standard/export.py
	settings.py