listen only to localhost

[beshoo]

I think this has to be add , so not DDos Attack to the port !

[loretoparisi]

@beshoo you are right, I have added a host parameter to the server.listen:

$ export PORT=3000
$ export HOST=localhost
$ export MODEL=data/lid.176.ftz
$ node server.js 
model loaded
server is listening on 3000

Thanks, closing then!