Log Message:
converters/dvisvgm: import dvisvgm-2.1.3

Packaged for wip by Kamil Rytarowski, with some updates and cleanups by me.

dvisvgm is a utility for TeX/LaTeX users. It converts DVI and EPS files to the
XML-based scalable vector graphics format SVG. The latest releases support
standard DVI files (version 2) as well as DVI output created by pTeX in
vertical mode (version 3), and XeTeX (versions 5 to 7, also known as XDV).