Allow creation of new invoice off customer
Merge pull request #97 from surfacedamage/customer-create-upcoming-invoice

Allow creation of new Invoice off Customer
Added unit test for respond_to
Implemented #respond_to?
Override #respond_to_missing? instead
Fall back to #respond_to? if ruby version is lower than 1.9.2
cleaning up a pull request from @thomasbrus
whoops, respond_to? cannot be protected
Add ruby 2.1.0 to travis config
Merge pull request #108 from timcraft/travis-ruby21

Add ruby 2.1.0 to travis config
Also uncomment legacy methods
Support deleting subscription discounts
Merge branch 'master' of github.com:stripe/stripe-ruby into ms