Test case for ValidationBlock not called

Validation Block doesnt get called as part of forceInsert method. When
pushing a document to sync gateway, the validation block should be called
during replication, but seems to be ignored.

Issue #: https://github.com/couchbase/couchbase-lite-java-core/issues/206
Fix the TestCase by checking for current revision

The Document object is created everytime and it doesnt make any sense to check if
that object is null. Instead the currentRevision will be null if the validation
actually failed.

Also, removed the validation and made sure that the same document was fetched properly
Issue #206 - edit test per comment "The second pull replication won't add the document.."

https://github.com/couchbase/couchbase-lite-java-core/issues/206#issuecomment-44352921
Revert "Fix bugs in previous PR & got more tests to pass"

This reverts commit 25e18a976b9020dc509a862bbe51c99fc87fca94.
Revert "Fixes for issues 280, 283, 285, 287 & 299"

This reverts commit 6d6576bb8a9685ce7841a938a59b57e57aa6d022.