Remove 7z dependency

[codebycaleb]

Unix systems come with zip by default, I believe. I don't think anything comes with 7z installed. Instead of installing 7zip myself, I swapped my local install to these commands and had no problems. -r is for recursive, -q is to silence the output of "adding ..." for each file that is added.

[Rob--W]

Compared to zip (from info-zip.org, version 3.0), 7z provides a better compression, stores files in a predictable order, and yields reproducible builds.

Because of the last two features, I'll keep 7-zip for now. I'll leave the PR open in case anyone else also wants to build without installing 7z.