Alternative IDEs - default to VS Code

[svenefftinge]

Theia has been the only interface to Gitpod workspaces. While it is very powerful and close to VS Code it is not VS Code and there are some subtle changes and more importantly, Theia tends to lag behind a bit. Furthermore, keeping up with VS Code has been a lot of effort while there is no real value for Gitpod users to use Theia if they really would like to use VS Code. Since VS Code changed their architecture within their open-source codebase to support running in browsers (codespaces needed that) we can use that project directly.

The real value in Theia is the flexibility to customize it deeply and build entirely new IDE-like products based on that. This wasn't supported in Gitpod previously. In order to allow teams to bring their own Theia (or other Web IDEs) we are allowing to configure Gitpod with your own IDE-specific docker image (#2419 (comment)).

The goal for this epic is to bring the current preview version of code to a state that it can replace the default Theia-based IDE and at the same time allow users to come up with their own version of Theia or other Web-based IDEs.

Actionable Items

See https://github.com/gitpod-io/gitpod/issues?q=is%3Aissue+label%3A%22editor%3A+code%22+is%3Aopen