MB-18846: Update minimum cmake version required
MB-18846: Update minimum cmake version required

Minumum CMake version required to support OBJECT
library types is 2.8.8.

Change-Id: Ic4dae5d41b6c4790eba2fec89cb090d0907f46cf
Reviewed-on: http://review.couchbase.org/61861
Reviewed-by: Chiyoung Seo <fcffc23db27b19ee4ebba46695ee6b50e09216a2@couchbase.com>
Tested-by: buildbot <80754af91bfb6d1073585b046fe0a474ce868509@couchbase.com>

couchbase/forestdb,hisundar/forestdb,hisundar/forestdb,couchbase/forestdb,wurikiji/forestdb,wurikiji/forestdb