Don't use absolute path for cmake.exe

Change-Id: Idb0352d6a357175d3809da15a708a2db86013a84
Reviewed-on: http://review.couchbase.org/29583
Reviewed-by: Trond Norbye <trond.norbye@gmail.com>
Tested-by: Trond Norbye <trond.norbye@gmail.com>
genconf moved

Change-Id: Ied8580ff163cf1223d267f363a6b87fcbc7e3b2f