Split setup in two for easier integration of usptream changes

[LoricAndre]

When the upstream setup file changes, integrating those changes can be complicated if you have custom steps. It would be nice to split the file in 2 parts, one functional and one for configuration, and maybe create a helper function for symlink_*.

[LoricAndre]

I can work on it, but I'd like some input first. This might require putting everything in functions, having those functions in one or more files, then having a main file sourcing those and the config file and calling everything.

[NNBnh]

Hello @LoricAndre, thank you for the suggestion.
I've moved the template directory structure into its own repo SSB template repo (later i will stick everything's together using Git submodules)
Tomorrow I will start split the main code file into smaller pieces, improve the code quality, update the README.md file and write a wiki for this project... small doc on the setup file :(
I hope we can make this done on next week.

[NNBnh]

Done in #5af58dc