see https://orgmode.org/manual/Checkboxes.html
We're deviating from Org mode regarding the assigned css classes but the chosen
classes feel better than (on, off, trans) and it's not like the export matches
1:1 otherwise.
While adding another test case from the goorgeous issues it became clear that
inline markup and html entity replacement were erronously applied to raw text
elements like inline code =foo=, src/example/export blocks, example lines,
etc.
To correctly handle those cases in both org and html exports a new
parseRawInline method had to be added.
Also some misc html export whitespace fixes and stuff
Also dismissed implementing colgroups for now - had it but didn't like the
added complexity for a very questionable benefit - i've actually never used
that feature of org tables...
... hopefully correctly
This will hopefully improve ease of developing (more granular test results) and
prepares us for adding example org->html renders for gh-pages
