gplugin/gplugin

Clean up stuff to prepare for a release.
develop
2020-07-23, Gary Kramlich
ed8e701cc2b1
Clean up stuff to prepare for a release.

Bump the version numbers and tweak the changelog a bit

Fix some broken links

sort the meson options by name

Add the trailing / to the latest docs and remove the link for the stable docs

Update HACKING.OSX to reflect the current state of homebrew

Reviewed at https://reviews.imfreedom.org/r/38/
There are a few notes about building on OSX.
First off, building has *ONLY* been tested against homebrew. If you want to
support fink or macports, please let me know and I will merge your pull
request.
Currently there is no known way to build the Perl loader on MacOS. So you
**MUST** run meson with `-Dperl=false`.
## Lua
For the Lua loader to work, you need to install `lgi` from luarocks either
systemwide or to a virtual environment created by LuaDist, vert, or something
along those lines, then you just need to run `luarocks install lgi`.
## Python
If you're using homebrew, you need to install `pygobject3`.