Removed unneccessary function instantiation.

Made the rest handler be a global callback rather than,
a per-operation one.  This stops us from compiling the
function for every operation.

Change-Id: Ibf191a8ec021eaae117f7d2b0cb690451d1c9230
Reviewed-on: http://review.couchbase.org/30187
Reviewed-by: Mark Nunberg <mnunberg@haskalah.org>
Tested-by: Brett Lawson <brett19@gmail.com>