Gitpod integration

[svenefftinge]

This PR adds a contributing section including support for Gitpod, a free online dev environment for GitHub, that starts the open-source Theia editor in a browser backed by a container with a full terminal.

This way contributors and other interested developers can start coding and trying fx with a single click right in the browser. I configured the startup so that the following tasks get executed (similar to the description for local dev):

npm install
npm run build
./dist/fx-linux package.json

Here is what it looks like:

You can try it out yourself:

[frextrite]

Hi @svenefftinge
I wanted to try out the demo but the Gitpod link isn't working. I'm guessing once the .gitpod.yml is added to the repository that link would work?

[svenefftinge]

It should work, just not be properly configured. But it seems like today we have issues with a cdn.
See gitpod-io/gitpod#272.

What does not working mean?
What do you see?
Is there something in the dev tools console?

[frextrite]

At the time I wrote the comment, only a blank white canvas was loaded. I thought .gitpod.yml had to be integrated first for it to work. But later on, I saw the issue about CORS error and when I checked again, the error was showing up in the Developer Console. Sorry for not being clearer earlier.

[svenefftinge]

We see issues with a CDN today. Could be that you are suffering from that.
gitpod-io/gitpod#272

[svenefftinge]

Seems like there is a certain region for which the CDN sends bad headers today. Could you tell me where you are?

[frextrite]

Hi, due to security reasons I won't write it here, but it's on my profile.

[svenefftinge]

This CDN issue has been resolved.