Create a Composer package

[ejunker]

It would be really great if this library was packaged up as a Composer package.
http://getcomposer.org/
https://packagist.org/

[zackbloom]

I'm happy to review a PR if you care to submit one with a composer.json.

[ryanwinchester]

I made some composer packages:

• haPiHP fork https://github.com/ryawin/hubspot
• Laravel package: https://github.com/fungku/laravel-hubspot
• Rewrite with new endpoints: https://ryanwinchester/hubspot-php

Cheers