According to https://repology.org/repository/nix_unstable/problems, we have a
lot of packages that have http links that redirect to https as their homepage.
This commit updates all these packages to use the https links as their
homepage.
The following script was used to make these updates:
```
curl https://repology.org/api/v1/repository/nix_unstable/problems \
| jq '.[] | .problem' -r \
| rg 'Homepage link "(.+)" is a permanent redirect to "(.+)" and should be updated' --replace 's@$1@$2@' \
| sort | uniq > script.sed
find -name '*.nix' | xargs -P4 -- sed -f script.sed -i
```
LV2 is a portable plugin standard for audio systems, similar in scope to LADSPA, VST, AU, and others. The Calf audio plugin pack uses LV2 and Ardour3 has also been updated to support LV2 Plugins
