* Ensure payments, invoice and credit amount balance in the validator prior to saving
* additional payment validation rules and tests for processing payments
* Factories for credits
* Tests for payments
* Working on updating a payment
* Working on updating a payment
* fixes for updating a payment
* Working on Payment Tests
* More tests for payments, formrequests
* remove product_key as required from products
* Remove unnecessary save() on invoice
* Update copyright
* Working on Credit Repository
* Implement credits as a paymentable entity
* Add credit_id to transformer
* fix rules for update payment
* Fix random deleted_at keys in transformers
* Fix for password_protect check
* Set payment number on completed payment
* Fix for paymentables not returning
* Do not set invoice status to paid if only a partial amount of the invoice has been paid
* Fixes for OpenAPI Documentation + fix support for docs for PHP 7.4
* User update tests
* Add total_taxes to invoice table, implement addition create-test-data fields for item and invoice level taxes
* Allow payment amounts to be partial per invoice paid
* edge case tests for payments
* Allow per invoice payment amounts and allow direct payments which simply credit a clients credit_balance
* Fixes
