Fixes to partial update, tests in core, and Query.addEqualityFilter

Fixed partial updates which broke tests in core. Tracked down the test breakage to broken Query.addEqualityFilter and fixed.
Can we replace this with this call?

 org.apache.usergrid.persistence.model.entity.Entity cpEntity = new org.apache.usergrid.persistence.model
                .entity.Entity( entityId );

That way we're not double loading.  Just pushing the update down to the collection, then loading the merged entity to index.