Update README.rst

[daprezjer]

Adds the new Integer option you added recently to the documentation here.

Any chance I could get maintainer access? I'd like to suggest the other types and potentially other improvements, without having to go through the whole forking process.

[mathieujobin]

@daprezjer Thanks for your contribution.
Can I ask you to keep using your fork for a while? Other contributors can be very active without write access to the main repo. Let me know what overhead it causes you, because it should be almost the same.