CBLT-254:  capture output of upload-to-maven.sh into log file

Change-Id: Id545abd00f607a6026e83690b34157fe9a39a801
Reviewed-on: http://review.couchbase.org/35534
Reviewed-by: Philip Labee <philip@couchbase.com>
Tested-by: Philip Labee <philip@couchbase.com>