[p7zip_alone2] new package for 7-Zip

[nhz2]

This is the same as the p7zip recipe except using the Alone2 bundle, which supports many more formats, instead of the Alone bundle.

The RAR format is still being disabled with export DISABLE_RAR=1 because the RAR code has an unfree license.

I set the version to 1.0.0 because upstream is using CalVer, so it doesn't make sense to try to use the same version for the jll. Maybe it would make more sense to match the version of p7zip?

[fingolfin]

First off: Thank you for your contribution!

Matching the p7zip version sounds plausible (but how is that version "defined", i.e., why is it 17.7? Hum)

Besides that, would it perhaps make sense to also match the name more closely? E.g. p7zip_alone2 or something like that? Otherwise it's really confusing: I'd immediately wonder what the relation between p7zip and sevenzip_standalone is.

To that end, a comment in the build recipe added here (and ideally also in the original p7zip recipes) explaining the relationship would be helpful, I think.

[nhz2]

The name was from the Debian package https://packages.debian.org/trixie/7zip-standalone, but 7zip-standalone wouldn't work because it starts with a number and has a dash. Maybe p7zip_full would be better? Though on Debian https://packages.debian.org/trixie/p7zip-full refers to the version of 7zip that dynamically links to a 7z.so

[ViralBShah]

Should Alone2 somehow be in the package name?

Perhaps good for @giordano to take a look here.

[giordano]

Yeah, doesn't look like this is going to happen in Julia