Add multiple subscription functionality - first pass
Adding tests for Subscription.
Clearing out subscription code/tests from Customer.
Ensure delete parameters are passed through for subscriptions.
Merge branch 'multiple-subscriptions' of github.com:pat/stripe-ruby into ms
Revert "Clearing out subscription code/tests from Customer."

This reverts commit d6ebab33109ff2501ba9709d2ac1dd666be0ab67.
We'll support the legacy single-subscription API style
indefinitely, and also we generaly try to make it so that
people can use modern bindings with out-of-date API versions.
Also uncomment legacy methods
Support deleting subscription discounts
Merge branch 'master' of github.com:stripe/stripe-ruby into ms
Fixup old tests for new param style in test_subscription
Merge pull request #113 from jimdanz/ms

Ms