adding support for Banwire

Fixes #50
Minor tweaks to improve Braintree integration
Merging Skrill and USA Epay gems into Spree Gateway
bumping master spree requirement to 2.0 to match spree master
apparently the version needs to be really specific
Update Versionfile
added support for BalancedPayments

Fixes #59
Finish Balanced Payments Support.

Fixes #63
renamed Balanced to BalancedGateway to avoid namespacing issue with Balance gem for their API

Fixes #62
added test for BalancedGateway

Related to #62
Rename Stripe gateway to StripeGateway

Fixes #60
Specify spree as a dependency in Gemfile (so that we can use 2.0.0)
update Stripe payment method type to StripeGateway

Fixes #65
Fixing spelling mistake in preferred_discover_login attribute in Worldpay
gateway

Changing attr_accessible prefered_discover_login to include second r, so that world pay payment methods can be created / updated
no need for activemerchant dependency, as spree_core already has one
MAJORLY bump factory_girl_rails version
Remove debugger gem references from gemfile
Fix class reference for CheckoutController in spec
Move factory_girl_rails dependency to gemspec
add support for CardSave gateway

Fixes #70