* Allow for priority to be set on event emitters
* Add payment event emitters
* add new actions/status to checkout state context
* implement event emitters in payment data context
* refactor checkout state context to use new actions in event emitters
* refactor checkout processor to handle new event emitters
* fix type-defs for registered payment methods
* register observer for cheque payment method integration
* add inline todo
* fix sort
* fix tests and add test for priority usage in event emitters
* remove todo and just add explanatory comment
* condense sort logic
* lowercase test description
* abstract emitter callback to reduce code
* don’t process passed in errors if it’s undefined
* improve error response expectation for payment processing event observer
* restructure event-emit directory and convert emitters to promises
- also add emitEventWithAbort function
* implement event emitters as promises
* clean up logic
- return from for loop
- define response as const on each iteration.
- return true if loop completes successfully.
* rename event_emit folder to event-emit
- restructures `@woocommerce/base-context` imports so it pulls from `index.js` in the `base/context` folder. That way tree-shaking will be used if possible. This also helps with organizing the folder structure a bit better for the new contexts.
- Fixes all the various imports through the code due to the above change.
- Adds `CheckoutContextProvider`, `useCheckoutContext` and related files.
- Adds `PaymentMethodDataProvider`, `usePaymentMethodDataContext` and related files.
- Adds `ShippingMethodDataProvider`, `useShippingMethodDataContext` and related files.
- Adds typedefs used for the various context interfaces.
Darren Ethier