Updated Ruby Books

Deleted tryruby.org since it is available in the interactive file

free-programming-books.md

@@ -1386,7 +1386,6 @@ See also [TeX](#tex)
 * [The Bastards Book of Ruby](http://ruby.bastardsbook.com/)
 * [The Little Book Of Ruby](http://www.sapphiresteel.com/The-Little-Book-Of-Ruby)
 * [The Unofficial Ruby Usage Guide (at Google)](http://www.caliban.org/ruby/rubyguide.shtml) - Ian Macdonald
-* [Try Ruby](http://tryruby.org/)
 * [Why's (Poignant) Guide to Ruby](http://mislav.uniqpath.com/poignant-guide/) ([mirror](http://www.scribd.com/doc/2236084/Whys-Poignant-Guide-to-Ruby))