Invalid flowdock data breaks server.js

After a few minutes the flowdock api returns data that breaks the server.js servlet. The following response is reported from nodejs:
```
undefined:1
d":false,"last_activity":1383775812713,"last_ping":1384024150385,"website":nul
                                                                              ^
SyntaxError: Unexpected end of input
    at Object.parse (native)
    at Object.FlowDock.parseResponse (/home/vcap/app/server.js:153:16)
    at IncomingMessage.<anonymous> (/home/vcap/app/server.js:108:15)
    at IncomingMessage.EventEmitter.emit (events.js:95:17)
    at IncomingMessage.<anonymous> (_stream_readable.js:746:14)
    at IncomingMessage.EventEmitter.emit (events.js:92:17)
    at emitReadable_ (_stream_readable.js:408:10)
    at emitReadable (_stream_readable.js:404:5)
    at readableAddChunk (_stream_readable.js:165:9)
    at IncomingMessage.Readable.push (_stream_readable.js:127:10)
```