Take Atom as an example :https://atom.io/packages/listIt use Github and get zip and install it.Or a better one in my opinion :https://packagecontrol.io/ for SublimeIt host and control all the packages but is in a sync with personal or public repositories like Github or BitBucket :https://packagecontrol.io/docs/channels_and_repositorieshttps://packagecontrol.io/docs/submitting_a_package
And we should consider hosting :https://packagecontrol.io/statshttps://packagecontrol.io/about
Its not a small job
Git or other tools should not be forced to users.
Let's keep it simple initially as suggested by Kostas in mailling list.In fact I would like to have the technical discussion in the mailling list because there are people who will more likely participate.For example all Lazarus developers follow the list but not all follow this forum.