Fix tests until the year 2020 (-:
Bump ruby version used for tests
Merge branch 'master' of github.com:antifuchs/cl-stripe into update
fixed doc reference urls
Added support for stripe card api calls

 * https://stripe.com/docs/api#cards

This should allow attaching more than a single card to a customer, and
updating existing card expirations (etc) without needing to renter the
card.

re ADWolf:#1158