remove unused 'bummer' field from settings

- Also fixup cntl.c to better handle some opcodes

Change-Id: I61718896d445224e3da900fd85729533410740b4
Reviewed-on: http://review.couchbase.org/38082
Tested-by: Mark Nunberg <mnunberg@haskalah.org>
Reviewed-by: Brett Lawson <brett19@gmail.com>