set up for my files and skip login
adds AddMonthlyInvoiceUI
MonthlyInvoiceUI now handles one-off invoices
no link to Invoices from homeUI

now you can only get to MonthlyInvoices (I know this needs to be
renamed... and we can really delete regular invoices now).
Adds all fxns to MonthlyInvoice controller.

Now does Get, GetAll, GetByPaymentStatus, Delete, Update.
Also, Invoice renamed to OldInvoice.
renames InvoiceController and InvoiceSystem

They are now called OldInvoice__
Also, renames MonthlyInvoice to Invoice.
renames invoice boundary classes to OldInvoice_UI
renames MonthlyInvoiceUI classes to Invoice_UI
AddNewInvoiceUI previews no. of jobs and amount