feat: could be used as a basis for EU-wide VAT

[barry86m]

This could be done via amending Item Tax Template to include:

• A country select list
• Changing VAT rules drop down to "Domestic, EU, Rest of World"

That seems to allow the correct recording of info required to calculate the return in least three countries with EU VAT systems (UK, DE, MT). Might possibly need an exempt category?

The actual return in EU countries is often a lot more involved than it is in the UK, so creating the reports for other countries is likely to be a lot of work! With a suitable foundation

Sample Return Forms
UK VAT100 - VAT Return Form.pdf
Malta VAT Return Form.pdf
Germany Annual VAT summary 2020.pdf (I haven't got an English version, sorry!)