Add phpDocumentor comments throughout to improve IDE support

This addresses issue #2.

This also allows you to create documentation for all the classes and methods using [phpDocumentor](http://www.phpdoc.org/)
@mikealmond,

This is really great! Can I ask one more thing of you and ask you to submit your documentation changes separately from your functional changes. This will make organizing these PRs much easier and faster for us with a light team reviewing these requests. Thanks again for all your work. Really excited to see this documentation added to the wrapper!