Add Latex Cheat Sheet (#11002)

* Added Latex cheat sheet

* Update free-programming-cheatsheets.md

* Update free-programming-cheatsheets.md

more/free-programming-cheatsheets.md

@@ -31,6 +31,7 @@
 * [Kotlin](#kotlin)
 * [Kubernetes](#kubernetes)
 * [Language Translations](#language-translations)
+* [Latex](#latex)
 * [Machine Learning](#machine-learning)
 * [Markdown](#markdown)
 * [MATLAB](#matlab)
@@ -325,6 +326,11 @@
 * [Swift and C# Quick Reference - Language Equivalents and Code Examples](http://www.globalnerdy.com/wordpress/wp-content/uploads/2015/03/SwiftCSharpPoster.pdf) - Globalnerdy (PDF)
 
 
+### LaTeX
+
+* [Latex Cheat Sheet](https://gist.github.com/LKS90/252ac41bd4a173be35b0) - Lukas Schneider
+
+
 ### Machine Learning
 
 * [Machine Learning Cheat Sheet](https://www.datacamp.com/cheat-sheet/machine-learning-cheat-sheet) - DataCamp Team (HTML)