v2.0.0

After more than a year, it's time to mark and tag the first official release of this module.
It starts at 2.x as I used to call 1.x the versions that were part of an older collection for SILE 0.12.x, and at point proposed upstream to SILE -- until it eventually became the present 3rd-party module, ported to SILE 0.14.x with changes and improvements.