Add *Of properties to RefResolver

The RefResolver currently skips any part of the schema that contains
'allOf', 'anyOf' or 'oneOf'. This prevents proper resolving of
references ($ref) that are inside of an array that is part of the above
mentioned properties.
Add the three property names to the array that is used to execute
resolveArrayOfSchemas().

Author: hglattergotz

src/JsonSchema/RefResolver.php

@@ -116,7 +116,7 @@ public function resolve($schema, $sourceUri = null)
         // These are all potentially arrays that contain schema objects
         // eg.  type can be a value or an array of values/schemas
         // eg.  items can be a schema or an array of schemas
-        foreach (array('disallow', 'extends', 'items', 'type') as $propertyName) {
+        foreach (array('disallow', 'extends', 'items', 'type', 'allOf', 'anyOf', 'oneOf') as $propertyName) {
             $this->resolveArrayOfSchemas($schema, $propertyName, $sourceUri);
         }