Create a "How to setup Elixir" guide or point to a good one

[mudphone]

Then we can link to it from our meeting pages, for people that want to come to meetings prepared. There's a sort of start of one on the Institute Readme: https://github.com/hui-ad/institute#prerequisites (perhaps once we have something here, we can point that over here, since this is the main "help" site for the group).

[thgaskell]

asdf-vm/asdf was a good suggestion. Their Getting Started guide was extremely easy to follow. The brew installation made it even simpler.

Just setting up Phoenix requires:

• Erlang
• Elixir
• Nodejs

It definitely streamlines the installation process and is something someone could easily set up in half an hour (depending on download speeds) at one of the meetups.

Doesn't look like there's window support yet though 🤔

[mudphone]

That's good to hear. Thanks for suggesting that link. Do you think we should put it on the GETTING_STARTED.md file in this repo?