Added port details to prevent heroku app crashing on startup

Heroku app would crash if it is not able to assign to default port within 60 seconds. There are many work arounds like using Heroku Forward. Here is the log obtained by running 'heroku logs'

2013-12-13T13:40:10.808464+00:00 heroku[web.1]: Error R10 (Boot timeout) -> Web process failed to bind to $PORT within 60 seconds of launch
2013-12-13T13:40:10.808644+00:00 heroku[web.1]: Stopping process with SIGKILL
2013-12-13T13:40:12.323468+00:00 heroku[web.1]: Process exited with status 137
2013-12-13T13:40:12.338632+00:00 heroku[web.1]: State changed from starting to crashed
2013-12-13T13:40:12.340025+00:00 heroku[web.1]: State changed from crashed to starting
2013-12-13T13:40:15.458517+00:00 heroku[web.1]: Starting process with command `python main.py`
2013-12-13T13:40:52.508876+00:00 heroku[router]: at=error code=H20 desc="App boot timeout" method=GET path=/ host=talkwithme.herokuapp.com fwd="14.139.82.6" dyno= connect= service= status=503 bytes=
2013-12-13T13:41:15.612142+00:00 heroku[web.1]: Error R10 (Boot timeout) -> Web process failed to bind to $PORT within 60 seconds of launch

But by giving port details in Procfile seems to fix this issue.