Feature/documentation

This is to show off how the documentation can be auto generated using a tool such as https://readthedocs.org which IMHO we should be doing for all of our projects. You can see the auto generated docs at http://testing-documentation-for-new-bitpay-repository.readthedocs.org/en/latest/ which will be taken down once a final solution is found.

Some of the benefits to this is that we are off loading documentation hosting to a trusted 3rd party. It can also be downloaded via pdf and epub which we don't need to generate, RTD does that for us. It can be version controlled and autogenerated as the repository is updated.