Allow storage backed tree roots to provide a storage fetch for multiple predicate evaluations at once, allowing previous predicate expressions to be evaluated along with new ones, massively reducing the cost of subsequent db scans.
A few performance improvements/hooks
Further rewrite to make the way that we allow multiple index fallbacks make more sense
Merge branch 'inline_entity_tiles' into async_entities
Merge branch 'inline_entity_tiles' into async_entities
Merge branch 'inline_entity_tiles' into async_entities
Update StorageBackedTreeRoot.java

Updated comments/code as per PR review requests.
Merge branch 'inline_entity_tiles' into async_entities

Conflicts:
	backend/src/org/commcare/util/CommCareSession.java
Merge branch 'async_entities' of https://github.com/dimagi/commcare into async_entities
Merge branch 'master' into async_entities
Merge pull request #31 from dimagi/async_entities

Asynchronous Cached Entities