Data type check on redis array host info

RedisArray will segfault if you pass something other than strings
into your array of hosts.  This is invalid input (needs strings here)
but it shouldn't crash php.

Author: michael-grunder

redis_array_impl.c

@@ -44,7 +44,9 @@ ra_load_hosts(RedisArray *ra, HashTable *hosts, long retry_interval, zend_bool b
 
 	/* init connections */
 	for(i = 0; i < count; ++i) {
-		if(FAILURE == zend_hash_quick_find(hosts, NULL, 0, i, (void**)&zpData)) {
+		if(FAILURE == zend_hash_quick_find(hosts, NULL, 0, i, (void**)&zpData) ||
+           Z_TYPE_PP(zpData) != IS_STRING) 
+        {
 			efree(ra);
 			return NULL;
 		}