Migrate from lcb_timer_t to lcbio_TIMER

Change-Id: Icc771f890a5dec0e9b02babe247224cd516b1d41
Reviewed-on: http://review.couchbase.org/36249
Reviewed-by: Brett Lawson <brett19@gmail.com>
Tested-by: Mark Nunberg <mnunberg@haskalah.org>