ITP: Structuring and testing data, WSL support.

**What is the hypothesis?**

Adding instructions on how to use WSL with windows will save both the trainees and volunteers a lot of time (and pain). VSCode works with WSL (i.e gives you a UI and opening the terminal inside vscode will drop you into bash instead of powershell)

**Why is this important?**

1. A lot of trainees come with a windows laptop. We make it clear [here](https://programming.codeyourfuture.io/structuring-data/prep/#install-a-unix-based-os) that CYF does not support windows. However, a lot of trainees do end up attending a Saturday session with windows laptops and as volunteers we do end up having to debug windows issues (eg: "I installed nodejs on windows but it doesn't work").
2. Trainees might simply have not gotten around to dual booting linux, or perhaps find the process too complex. WSL can act as a temporary solution while they sort out dual booting.
3. A trainee even asked me to recommend them a used MacBook because they currently had a windows laptop which they thought was insufficient. Though they might have just wanted a MacBook and were looking for excuses to get one (wasn't very keen on dual booting linux), I didn't want to condone the idea that you cannot make do with what you already have. In this particular case, they were quite happy with WSL once they managed to get it working. Having a WSL based alternative to [this](https://programming.codeyourfuture.io/structuring-data/prep/#install-a-unix-based-os) page will IMHO make the program more inclusive.

**Next steps**

Would love to get the community's thoughts on this. I'd be happy to write up some WSL instructions if the community thinks that this will be useful.