Use private libconflate

Change-Id: Ie929ef27573f1bbdc898096c941b71bc6e7c5a1c
Reviewed-on: http://review.couchbase.org/28691
Reviewed-by: Trond Norbye <trond.norbye@gmail.com>
Tested-by: Trond Norbye <trond.norbye@gmail.com>