Use 7-zip to create official release ZIP archives with better compression (and same compatibility)

[Calinou]

7-zip can create fully-compatible ZIP archives that are smaller than the ones created by the reference InfoZIP tool (i.e. the zip command). This is done with the command 7z a -mx9 <folder>.zip <folder>.

For instance, the official 3.2 Linux 64-bit ZIP currently weighs 28.2 MB, but it could be recompressed to weigh only 27.4 MB. The difference isn't huge, but it will likely increase as Godot's binaries keep becoming larger over time. This should also help spare TuxFamily's servers a bit, considering how often Godot is downloaded 🙂

This should help with export templates even more. It might take a while to create optimized ZIPs in this case though, as 7z is quite slow in its maximal compression mode. I still think it's worth doing for stable releases at least (and maybe prereleases if time allows).

Edit: I just did a test with the 3.2 Mono export templates. The ZIP created by 7z is 480.6 MB instead of 490 MB.

Edit 2: On 4.0.alpha10, the 64-bit Linux editor ZIP is 46.8 MB when compressed using the above method instead of 47.9 MB. That's a saving of 1.1 MB 🙂