Merge pull request #6238 from nfauchelle/patch-2

Remove double quotes so example is not parsed.

model/Map.php

@@ -196,7 +196,7 @@ public function offsetSet($key, $value) {
 		}
 
 		user_error(
-			"SS_Map is read-only. Please use $map->push($key, $value) to append values", 
+			'SS_Map is read-only. Please use $map->push($key, $value) to append values', 
 			E_USER_ERROR
 		);
 	}