Issue #95 - unit test modifications, initial version was broken

After attempting an implementation for a fix, and rerunning the unit test, it still failed.  Digging into the unit test further revealed what appears to be a bug in the unit test (was calling wrong db api to get local stored lastSequence)
https://github.com/couchbase/couchbase-lite-java-core/issues/95
Issue #95 - unit test modifications, still was not reproducing issue using code before the fix.

1) silly workaround needed in test
2) had to hack the mulitpartUploader to call setLastSequence(), because it was not (even though it should have been to be on-par with the iOS code before the fix for this issue)
https://github.com/couchbase/couchbase-lite-java-core/issues/95