Use optimist npm module for handling phantomas options

[macbre]

As phantomas.js entry point uses node.js now (#151), we can use optimist module for handling options passed to the script.

[macbre]

Waiting for #152

[macbre]

From #163 (@plasticine)

I does not currently seem to be possible to pass along options to phantomjs when running phantomas.

CasperJS does this nice thing where it will pass any unrecognised config options down to phantom.

In my case I would like to set a few phantom specific options; --ignore-ssl-errors=true --cookies-file=cookie_jar, but that doesn’t seem to be possible.

[macbre]

Setting DEBUG env variable will emit debug info

$ DEBUG=* ./phantomas.js --url https://github.com/macbre/phantomas --verbose --no-externals --allow-domain .fastly.net
  phantomas nodejs v0.10.4 +0ms
  phantomas PhantomJS v1.9.2 installed in /usr/local/bin/phantomjs +4ms
  phantomas phantomas v0.10.1 installed in /home/macbre/github/phantomas +0ms
  phantomas URL: <https://github.com/macbre/phantomas> +0ms
  phantomas Options: {"version":false,"V":false,"help":false,"h":false,"disable-js":false,"no-externals":true,"silent":false,"verbose":true,"v":true,"analyze-css":false,"film-strip":false,"allow-domain":".fastly.net","format":"plain","timeout":15,"viewport":"1280x1024"} +0ms
  phantomas Running /usr/local/bin/phantomjs /home/macbre/github/phantomas/phantomjs/phantomas.js --no-externals --verbose --v --allow-domain .fastly.net --format plain --timeout 15 --viewport 1280x1024 --url https://github.com/macbre/phantomas +1ms
  phantomas Spawned with pid #5315 +3ms