Merge pull request #221 from tobexyz/feat/issue219

fix: process http 503 correctly issue #219

Author: tobexyz

yaacc/src/main/java/org/fourthline/cling/model/message/UpnpResponse.java

@@ -31,7 +31,8 @@ public static enum Status {
         PRECONDITION_FAILED(412, "Precondition Failed"),
         UNSUPPORTED_MEDIA_TYPE(415, "Unsupported Media Type"),
         INTERNAL_SERVER_ERROR(500, "Internal Server Error"),
-        NOT_IMPLEMENTED(501, "Not Implemented");
+        NOT_IMPLEMENTED(501, "Not Implemented"),
+        SERVICE_UNAVAILABLE(503, "Service Unavailable");
 
         private int statusCode;
         private String statusMsg;