- Added requirement for collective.stripe
- Added IStripeModeChooser and a stub get_stripe_mode method to FundraisingPage
- Added IStripeEnabledView to FundraisingPage to include Stripe.js
- Created an initial port of the Authorize.net DPM one time donation
  form to Stripe.  Form renders but is not recognized by javascript yet.
donation_form_stripe now loads with the same front-end interaction as
the Authorize.net DPM method, constructs a token on submit, and calls
the process_donation method which successfully processes the donation,
then drops to a pdb prompt for now.  Post payment implementation coming
soon
Stripe donation form now works with a few kinks to work out:
- Error handling works, but needs to be integrated into the page instead
  of a JS alert.
- After an error, form won't submit again.
Integrated Product Form with Stripe, included more of the donation form
styling
Pulled some images from ip.theme.fundraising that are relevant to the
generic form style

Implemented stripe donation form for Donation Product
Merge pull request #50 from innocenceproject/stripe

Merge Stripe Integration