Vietnamese language lacking the Vietnamese dong symbol & Auto build accent for Vietnamese characters

Thank you very much for adding the Vietnamese language to Affont and even making a Vietnamese template for it! I am about to release a new font that is dedicated to Vietnam's daily life! Here is something that I want to express for this font: We usually need to have the vietnamese dong U+20AB (₫), as this is Vietnamese currency. I was wondering if you can update it so it can include this character?

Another feature I would like to include is to be able to batch build the vietnamese character set, as most of them are very much repetitive which all these symbols and stuff. It will be a god save if you can include it!

I'm grateful for what you have done for this tool so far and I look forward for new updates!