Switch to gt for Word and html

In Quarto 1.2 there is a bug that flextables no longer appear in html. Fixed in pre-release 1.2.269.
So for the time being switched to gt()

Re ugly Word tables, that is
a) gt needs to output to raw html to have captions work until Quarto is able to understand xml
b) something with using a template trashes any html formatting (top border line)

This will get fixed once Quarto figures out how to recognize xml because then flextable will work.