replication change listeners switched back to use r.getStatus() instead of e.transition()

https://github.com/couchbase/couchbase-lite-android/issues/398
add bulk_get functionality to mockwebserver

and now mockPull test now passes on nexus 5.

for some reason, on device the batching is happening differently and triggering it to use bulk_get.  the test works in both scenarios now.

https://github.com/couchbase/couchbase-lite-android/issues/398