Added donation forms for PayPal.
Removed useless print statements.
Added basic PayPal donation form.
Outlined IPN endpoint for PayPal.
Fixed form.
Renamed WePay donation form.
Fixed host address checking during callback_uri definition for WePay requests.
Minor documentation tweaks.
Started work on IPN endpoint for PayPal. Added verification.
Added get_by_transaction_id method into Donation model.
Outlined IPN processor for PayPal.
Partially implemented creation of a new donation record for PayPal.
Fixed type errors.
Moved implementation of PayPal form into template.
Added support for custom variables passed via PayPal IPNs.
Added basic test for PayPal IPN processor.
Updated tests for donation views.
Updated tests for donation views (again).