Add section for crypto

free-programming-books.md

@@ -21,6 +21,7 @@
     * [Web Performance](#web-performance)
     * [MOOC](#mooc)
     * [Professional Development](#professional-development)
+    * [Cryptography](#cryptography)
 * [Ada](#ada)
 * [Agda](#agda)
 * [Android](#android)
@@ -363,6 +364,10 @@
 * [Confessions of an IT Manager](http://download.red-gate.com/ebooks/DotNet/Confessions_IT_Manager.zip) *(RedGate, By Phil Factor)*
 
 
+####Cryptography
+* [Handbook of Applied Cryptography](http://cacr.uwaterloo.ca/hac/index.html)
+
+
 ###Ada
 * [Ada 95: The Craft of Object-Oriented Programming](http://faculty.cs.wwu.edu/reedyc/AdaResources/bookhtml/contents.htm)
 * [Ada Distilled](http://www.adapower.com/pdfs/AdaDistilled07-27-2003.pdf) (PDF)