Added tldr notes to the knowledge base

knowledge base/tldr.md

@@ -0,0 +1,17 @@
+# TL;DR
+
+```shell
+pip3 install tldr                   # official python client
+brew install tealdeer               # rust client
+sudo port install tldr-cpp-client   # c++ client
+```
+
+## Further readings
+
+- [website]
+- [live demo]
+- project's [github] page
+
+[github]: https://github.com/tldr-pages/tldr
+[live demo]: https://tldr.ostera.io
+[website]: https://tldr.sh/