Adds SpreedlyCore Gateway support

Fixes #148
Send invoice number in auth_capture method of Authorize.net CIM getaway

Fixes #147
Pass billing address to braintree to allow address verification

Fixes #157
Add coverage to gitignore.
fix specs
Merge pull request #167 from j-mcnally/fix_card_verify_with_braintree-2-1-stable

fixes specs for braintree on 2-1-stable to allow merging of #166 to 2-1
Change card.type to card.brand to match Stripe API change.
Fixes #170
Fix sending address lines. Fixes #171