Building Eclipse Plugin from Github, or how to archive it?

I have a Ubuntu 16.04 computer with eclipse installed that I would like to use with OpenFrameworks. For convenience, I would like to make an offline archive of the plugin for when I use a different computer, or, like now, want to use it on a new one.

Eclipse has the capability of adding plugins via directory or via zip file, not just URL, but if I clone the plugin from the OF github page, I can’t use it either as zip or as a directory for adding the plugin. Since I assume that’s the plugin source code on Github, how do I process it into a local archive or repo for installing it, and how do I use it?

What sort of magic happens between the github files and the strange link on the Linux Install Page? Weirder still, following the link in browser or with wget fails, yet Eclipse has no issues.

I have Eclipse 3.8.1 via default Ubuntu sources. I’d like to install the plugin on the new computer and simultaneously create an archive for easier installation next time.

This is an update of a similar question that I posted a while ago.

you need to install the eclipse plugin developer plugins to be able to import the source into eclipse itself and produce an archive from there