Add Bash Scripting Cheatsheet (#4852)

free-programming-cheatsheets.md

@@ -1,5 +1,6 @@
 ### Index
 
+* [Bash](#bash)
 * [Clojure](#clojure)
 * [Data Science](#data-science)
 * [Git](#git)
@@ -16,6 +17,11 @@
 * [SQL](#sql)
 
 
+### Bash
+
+* [Bash Scripting cheatsheet](https://devhints.io/bash) Devhints (HTML)
+
+
 ### Clojure
 
 * [Clojure Cheatsheet](http://clojure.org/cheatsheet)