Issue #331 - convert tests to mockwebserver

https://github.com/couchbase/couchbase-lite-android/issues/331
CBLT-318 - this had the wrong artifact id

http://www.couchbase.com/issues/browse/CBLT-318
Issue #331 - testPullerNoAttachments() and testPullerNoAttachmentsWithSecondPull() working

https://github.com/couchbase/couchbase-lite-android/issues/331