4.2.0

Build encompasses changes from OAS 2.1.11 thru 2.1.13
https://github.com/XeroAPI/Xero-OpenAPI/releases/tag/2.1.13

Improved exception handling heriarchy

ACCOUNTING
Added additional enum for Employee endpoint
Remove "Contact" as a req. param for Bank Transactions
Add DELETED enum to QuoteStatusCode in Quote schema

AU PAYROLL

Change LeaveLoadingRate from integer to double
Remove CalculationType requirement for EarningLine
restored the type of AccureLeave in ErarningsRate to boolean

UK PAYROLL
Change method getPayslips to getPaySlips
Add missing earningsRates
Add missing deduction type enums
Add missing deductible category enums