Upgrade to spymemcached 2.10.2

Change-Id: I1aed2cbcd5552686b5a141828edf75d6bfb8afd1
Reviewed-on: http://review.couchbase.org/30051
Tested-by: Michael Nitschinger <michael.nitschinger@couchbase.com>
Reviewed-by: Trond Norbye <trond.norbye@gmail.com>