wip: adding payments with add debt call
major restructure to support multiplement direct debit providers
adding ezidebit tests with mocks
initial ezidebit customer tests passing
refactored to generic parsing method
refactored to generic parsing method
cleaned up response and request properties
start of securepay payment provider implementation
making xml requests more dynamic
raise error message on responseCode other than 0
changed endpoint to use correct url for periodic and payments
Merge branch 'master' of https://github.com/jstaff/directdebit-ruby