OGM-396 Adding TestHelper#getCurrentGridDialect()
OGM-396 Misc. generics related improvements
OGM-396 Upgrading to JUnit 4.11
OGM-396 Creating new dialect facet OptimisticLockingAwareGridDialect for dialects with atomic find-and-update semantics
OGM-396 Removing some redundant code
OGM-396 Adding support for atomic find-and-delete operations
OGM-396 Adding more tests
OGM-396 Adding test and fixing bug for state-based optimistic locking
OGM-396 Dealing with attempts to delete an already deleted record
OGM-396 Adding test for optimistic locking check during merging
OGM-396 Incorporating review remarks