Change "INVOICE" to "TAX INVOICE"

[Andrew Greig]

Hi all, 

no I am not yelling.  I checked the archives on altering the Invoice,
and have looked at all the .scm files I can find that seem to have
anything to do with a Fancy invoice.  I am very close to getting an
acceptable layout but in Australia we need to have "Tax Invoice" on our
document and not just "Invoice"

This has not been easy to find.  Can someone refer me to the correct
file to edit, please?  I was hoping it would be as easy as slipping TAX
inside the quotes.  

This is where my efforts have been

/usr/share/gnucash/guile-modules/gnucash/report
easy-invoice.scm
fancy-invoice.scm
invoice.scm
business-reports.scm

Many thanks
Andrew Greig
Australia