[tex4ht] SVG production

[Michal Hoftich]

Quoting Karl Berry (2017-02-01 23:39:57)
> dvips|gs is probably considerably more widely available than
> dvipng in principle, but not among people using our latest tex4ht.
> 
> So by all means, go ahead and change things to use dvipng. I'll wait for
> that to update TL ... --thanks, karl.
> 

OK, so dvipng is used by default. I choose 

    dvipng -T tight -D 144 -bg Transparent

as default parameters. It uses slightly larger resolution than the
previous settings, which were too small IMHO. If someone want to use the
Dvips + GS way, it can be used with `-c convert` option for t4ht (so
something like htlatex filename "xhtml" "" " -c convert"). SVG output
can be chosen with `\Configure{Picture}{.svg}` in the .cfg file.

Michal