fix php_memcached.c:3737:21: warning: variable 'intern' set but not used
fix warning: 'payload' may be used uninitialized in this function (ok, was a false positive)
Fix php_memcached_server.c:589:49: warning: array subscript is above array bounds
php_memcached.c:3317:11: warning: 'buffer' may be used uninitialized in this function (just to make gcc happy)
Fix warning: 'status' may be used uninitialized in this function
Fix php_memcached.c:781:45: warning: 'orig_cas_flag' may be used uninitialized in this function (again... just to make gcc happy)
Merge pull request #131 from remicollet/issue-220RC1

Fix build warnings