Don't nest macros for defining constants

Otherwise some of our operation markers get lost

Change-Id: Idd95a4e3111c10f24ca489fbe79fc9f3a8bb2f22
Reviewed-on: http://review.couchbase.org/28996
Tested-by: Mark Nunberg <mnunberg@haskalah.org>
Reviewed-by: Brett Lawson <brett19@gmail.com>