[WIP] Visual Studio Code IDE Documentation

As the documentation already improved significantly since the issue was created, the improvements planed for this PR are minor. The main "feature" planed for this PR is, how docker image(s) can be used to develop & debug a binding without actually installing openHAB on the development system.

This also simplifies to work with different versions (e.g. if you analyze an issue of a released version, or if you develop/test on nightly builds). The proposed changes should also help to improve developer experience, e.g. add-on's and task configurations to locally check code formating rules (linting).

Fixes openhab#2276
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## TODO
- [ ] ....

.nvmrc

@@ -0,0 +1 @@
+16.20.1