Removes unused coupon, address, and currency 'meta' parameters

Signed-off-by: Christopher Rogers <chrissrogers@gmail.com>
Applies RecurlyError name to code by default

Signed-off-by: Christopher Rogers <chrissrogers@gmail.com>
Fixes issue with PricingPromise#done incorrectly chaining its reprice call

Signed-off-by: Christopher Rogers <chrissrogers@gmail.com>