Add per-language binder demo links

Author: krassowski

README.md

@@ -2,11 +2,12 @@
 
 [![tests](https://github.com/jupyter-lsp/jupyterlab-lsp/workflows/CI/badge.svg)](https://github.com/jupyter-lsp/jupyterlab-lsp/actions?query=workflow%3ACI+branch%3Amaster)
 [![Documentation Status](https://readthedocs.org/projects/jupyterlab-lsp/badge/?version=latest)](https://jupyterlab-lsp.readthedocs.io/en/latest/?badge=latest)
-[![Binder](https://mybinder.org/badge_logo.svg)](https://mybinder.org/v2/gh/krassowski/jupyterlab-lsp/master?urlpath=lab%2Ftree%2Fexamples%2FPython.ipynb)
+[![Python Demo](https://img.shields.io/badge/demo-Python-blue)](https://mybinder.org/v2/gh/jupyter-lsp/demo-python/main?urlpath=lab)
+[![R Demo](https://img.shields.io/badge/demo-R-blue)](https://mybinder.org/v2/gh/jupyter-lsp/demo-R/main?urlpath=lab)
+[![Julia Demo](https://img.shields.io/badge/demo-Julia-blue)](https://mybinder.org/v2/gh/jupyter-lsp/demo-julia/main?urlpath=lab)
+[![Binder](https://img.shields.io/badge/launch-dev_version-blue)](https://mybinder.org/v2/gh/jupyter-lsp/jupyterlab-lsp/master?urlpath=lab%2Ftree%2Fexamples%2FPython.ipynb)
 
-> _This project is still maturing, but you are welcome to check it out, leave feedback and/or a PR_
-
-Quick Links: **[Installation](#installation) | [Configuring](./docs/Configuring.ipynb) | [Changelog](./CHANGELOG.md) | [Roadmap](./docs/Roadmap.ipynb) | [Contributing](./CONTRIBUTING.md) | [Extending](./docs/Extending.ipynb)**
+**[Installation](#installation) | [Configuring](./docs/Configuring.ipynb) | [Changelog](./CHANGELOG.md) | [Roadmap](./docs/Roadmap.ipynb) | [Contributing](./CONTRIBUTING.md) | [Extending](./docs/Extending.ipynb)**
 
 ## Features