Updating Spymemcached to 2.10.5

Removing the shutdown method because it is now part of the
inherited spymemcached connection.

Change-Id: Icf881d3de30f11655920091600badba3987e615d
Reviewed-on: http://review.couchbase.org/33285
Tested-by: Michael Nitschinger <michael.nitschinger@couchbase.com>
Reviewed-by: Brett Lawson <brett19@gmail.com>