Small refactoring for UnitOfWork::doMerge()
Support non-null, falsey identifiers and getIdentifierObject() in more places
Removed scheduled extra updates, move id generation to UnitOfWork::persistNew() and throw exception when DocumentManager::createDBRef() is called on an object without an identifier.
add test failure.
Refactor UnitOfWork::doMerge() based on ORM
add failing assertion to DetachedDocumentTest
port remaining functionality from orm merge() functionality.
fix GH580Test failure from exception not cleaning up queuedInserts
Remove postInsertIds from DocumentPersister and UnitOfWork.
Add missing CmsUser::phonenumbers mappedBy configuration.
Add BaseTest::createTestDocumentManager() convenience method.
add tests for various types of identifiers.
cast identifier values on persist.
fix date _id type.