Glad you're interested in my dotfiles! I use them a lot to build up new systems...
It's definiately an active work in progress, and there isn't going to be a done of documentation, so feel free to dig deep and ready some of my shell scripts. Fork me if you wish, probably don't pull request, unless you're amazing with bash, and want to school me.
I started keeping track of different OS versions and version numbers, for some granular control - this is kind of cumbersome, but needed because I am running a range of OS...
I mostly use OS X 10.12 Sierra, Ubuntu LTS 16.04, and sometimes Raspian for hobby projects.
Cheers, Jacob