MB-100: remove btrc from common debug script

Change-Id: Icfcddfd3b884e38022e718a1435d2aefe3bbe4de
Reviewed-on: http://review.couchbase.org/27594
Reviewed-by: Pavel Paulau <pavel.paulau@gmail.com>
Tested-by: Pavel Paulau <pavel.paulau@gmail.com>