Add install instructions

[logankilpatrick]

Hey all, It would be nice to have detailed install instructions. I am currently adding my first exercise for the Julia track and it's a bit unclear how I can use this tool.

[SleeplessByte]

I agree.

Most repositories have a configlet fetch command, that fetches the executable from the releases page here. That's basically all there is to "installing".

[ErikSchierboom]

I learnt most of it by examining other repos, so I definitely agree that we could improve on the instructions.