Added CMake courses (#6150)

* Added CMake courses

* fixed alphabetical order build error

* fixed build error (I hope)

* removed riptutorials

books/free-programming-books-langs.md

@@ -32,6 +32,7 @@ That section got so big, we decided to split it into its own file, the [BY SUBJE
 * [Chapel](#chapel)
 * [Cilk](#cilk)
 * [Clojure](#clojure)
+* [CMake](#cmake)
 * [COBOL](#cobol)
 * [CoffeeScript](#coffeescript)
 * [ColdFusion](#coldfusion)
@@ -534,6 +535,13 @@ That section got so big, we decided to split it into its own file, the [BY SUBJE
 * [The Clojure Style Guide](https://github.com/bbatsov/clojure-style-guide)
 
 
+### CMake
+
+* [An Introduction to Modern CMake](https://cliutils.gitlab.io/modern-cmake/) - Henry Schreiner (HTML)
+* [CMake Tutorial](https://cmake.org/cmake/help/latest/guide/tutorial/index.html) (HTML)
+* [Quick CMake tutorial](https://www.jetbrains.com/help/clion/quick-cmake-tutorial.html) (HTML)
+
+
 ### COBOL
 
 * [COBOL Programming Fundamental](http://yusman.staff.gunadarma.ac.id/Downloads/files/33460/COBOL_Programming_Fundamental.pdf) (PDF)