[docs] Add Julia section

[jankeromnes]

Initial draft.

[svenefftinge]

I think we should remove the "not support" part of the sentence.

[svenefftinge]

And it would be great to not only point to n example but rephrase the steps here.

[JesterOrNot]

Looks good!

[JesterOrNot]

@jankeromnes
maybe underneath the link add a open in Gitpod button

Julia

🚧 Please help improve this guide by editing it.

While Gitpod doesn't currently support Julia out-of-the-box, it's easy to set up your Julia project in Gitpod.

A great example for a ready-to-code Julia dev environment is JesterOrNot/Gitpod-Julia.

# Julia

> 🚧 Please help improve this guide by [editing it](https://gitpod.io/#https://github.com/gitpod-io/website/blob/master/src/docs/julia_in_gitpod.md).

While Gitpod doesn't currently support Julia out-of-the-box, it's easy to set up your Julia project in Gitpod.

A great example for a ready-to-code Julia dev environment is [JesterOrNot/Gitpod-Julia](https://github.com/JesterOrNot/Gitpod-Julia).

[![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/#https://github.com/JesterOrNot/Gitpod-Julia)

[jankeromnes]

Superseeded by #376.