Issue #5: Added the merchant_notes attribute to the SubscriptionAdjustment class
fixed the typo in client.rb that made delete not work. Added a delete method that can take parameters instead of acting on an object. Created a spec test for the subscriptionadjustment class
added save conditions to delete! and fixed tests
added not saved test to delete! method
Merge pull request #6 from LelandNordin/master

Issue #5: Added the merchant_notes attribute to the SubscriptionAdjustme...