Allow passing One Time Password to login

Include the X-GitHub-OTP header if otp option is passed in order to
support two factor authentication
Merge pull request #80 from jgable/twoFactorAuth

Allow passing One Time Password to login
Add hooks endpoints for Repo

- Add hooks for listing hooks
- Add createHook for creating a hook
- Add description to README
Merge pull request #79 from jgable/repoHooks

Add hooks endpoints for Repo