Suggestion to rearrange VAT field usage

[fixundfertig123]

Hello everyone.

Trying to get in ERPNext and being from Germany I found this app. That's a great help. Thank you for all your work!!!

I came across a problem of the current VAT field usage and I hope I used the app correctly. Please excuse if I misunderstood something! Having a slight IT and business background I would suggest to the VAT field to every customer, supplier and company (in the registration field) and loose couple those to the VAT ID check. Since a VAT ID can be added and revoked from customers and supplier at any point this in later terms would ease purchase orders, sales orders, ...

However, I am not yet fit in terms of the patch structure of Frappe (ensuring backward compatibility) so I created a forked branch: https://github.com/fixundfertig123/erpnext_germany/tree/pu/changeRequest/vat

This change request would in parts picks up the problem addressed at #29.

Please ask any question there are.

Kind regards