Add Oney Simulation API

• Add OneyPaymentSimulation class to handle the /oney_payment_simulations API endpoint

Add missing `billing` and `shipping` entities to `payment` resource

Update __version__.py

Bump version

Add accounting reports

• Add AccountingReport class to handle the new /accounting_reports API endpoint.

Add API version setting

• Add API version setting.
• Fix tests.
• Move CI to Github Actions.

V1.2.1

• Require pyOpenSSL>=0.15 to prevent random failures.
• Log more errors in case of request failure.

V1.2.0

• NEW: Support for Customers and Cards. (see official documentation)

• NEW: Add ability to abort payment objects.

  payment.abort()
  

• NEW: This library is now under MIT Licence (Issue #4).

• Minor fixes in tests.

• Add this changelog.