Merge pull request #676 from RNanoware/master

Added book "Agile Java" to "Java" section

free-programming-books.md

@@ -897,6 +897,7 @@
 
 
 ###Java
+* [Agile Java](http://www.langrsoft.com/ftp/agileJava/) - Jeff Langr
 * [Animation/Games in Java](http://www.heatonresearch.com/articles/series/3)
 * [Apache Jakarta Commons: Reusable Java Components](http://ptgmedia.pearsoncmg.com/images/0131478303/downloads/Iverson_book.pdf) - Will Iverson
 * [Artificial Intelligence - Foundation of Computational Agents](http://artint.info/html/ArtInt.html)