[memcached] add fixes for memcached

Author: JorgenEvens

cache.php

@@ -177,6 +177,9 @@ function memcache_mem( $key ) {
         if( $key == 'hash' )
             $key = 'hash_bytes';
 
+        if (!is_array($memcache_stats))
+            return 0;
+
         $result = 0;
         foreach( $memcache_stats as $server )
             $result += empty($server[$key]) ? 0 : $server[$key];
@@ -215,6 +218,9 @@ function memcache_ref() {
 
         $items = $memcache->getAllKeys();
 
+        if (!is_array($items))
+            return array();
+
         $keys = array();
         foreach( $items as $item ) {
             $keys[$item] = memcache_get_key($item);