CBLT-254:  upload android package as AAR file

Change-Id: I11f58a3db05f787b8a11897bd19dcff5a161dd59
Reviewed-on: http://review.couchbase.org/35564
Reviewed-by: Philip Labee <philip@couchbase.com>
Tested-by: Philip Labee <philip@couchbase.com>