Add more info if WIFEXITED failed in testapp
Add more info if WIFEXITED failed in testapp

Change-Id: I046b028c6780e06a9219db14bca8b730d438b9f0
Reviewed-on: http://review.couchbase.org/69296
Tested-by: buildbot <80754af91bfb6d1073585b046fe0a474ce868509@couchbase.com>
Reviewed-by: Jim Walker <1cd02e31b43620d7c664e038ca42a060d61727b9@couchbase.com>

daverigby/memcached,daverigby/memcached,daverigby/memcached,couchbase/memcached,couchbase/memcached,daverigby/kv_engine,daverigby/kv_engine,daverigby/memcached,couchbase/memcached,daverigby/kv_engine,couchbase/memcached,daverigby/kv_engine