Banking System Only Use Account Number
- Removes usages of AccountCode when only using AccountNumber in the banking system.
- Changes the BankAccountType to only store the account number and not the code.
- Removes setting the opening account code directly, since it's only used in unit tests.
- Adds missing unit tests for the general ledger.
- Fixes the expected checksum for the reconciliation unit tests.
- Adds passing the ledger account codes.
- Adds a function to find an account code from its account number.
- Adds missing unit tests.
- Renames the member function bankAccountCodes to bankAccountTypes in a bank ledger.
- Fixes adding an existing bank account to its widget.
Closes #68 (closed)