Allow build from source bundle

Change-Id: Ic0f6690334607411f9ce8cdf560c67fe5a4d234a
Reviewed-on: http://review.couchbase.org/36216
Reviewed-by: Chiyoung Seo <chiyoung@couchbase.com>
Tested-by: Trond Norbye <trond.norbye@gmail.com>