CBLT-198:  turn on DEBUG for set_jenkins_default_param.pl

Change-Id: Ia6ac1816a957dfb5a22068fb6ecd60930344a3a0
Reviewed-on: http://review.couchbase.org/34130
Reviewed-by: Philip Labee <philip@couchbase.com>
Tested-by: Philip Labee <philip@couchbase.com>