Add Taiwan VAT 5%

The most common VAT in Taiwan is 5%. This commit adds the VAT for Taiwan.

Signed-off-by: Ying-Chun Liu (PaulLiu) <paulliu@debian.org>
Handle updates for Taiwan VAT.

Signed-off-by: Ying-Chun Liu (PaulLiu) <paulliu@debian.org>
Merge pull request #2150 from grandpaul/taiwanvat

Add Taiwan VAT 5%