Added new apis to query users and fixed EF.Inmemory

@HaoK @divega 

Adding new apis for query users with claims and users in roles
> ... and verify the query

If the comparisons are not included in the WHERE clause we should talk to @anpete. Since we are currently evaluating the clause again in-memory it sounds reasonable that we could support translating `Equals()` with some values of `StringComparison` to predicates in the WHERE clause loosely as long as the rows returned from the database are a superset of the matching rows with in-memory semantics.

If this gets scoped out of EF7 RTM we can always write the query explicitly the way we want it, e.g. with a simple `Equals()` (assuming that one does get translated to an equality predicate in the WHERE clause) and the preforming the final filter in-memory with the right StringComparison value.