Add section for crypto
Add a section for unix tools
Add OpenGL Red Book
Update URL to Algorithms textbook - this URL is broken
Add Philip Greenspun books - Software Engineering for Internet Applications
and SQL for Web Nerds
Add Lessig's "The Future of Ideas"
Add "The Big Online Book of Linux Ada Programming"
Add a pair of C++ books
Add ORA's "Learning Debian GNU/Linux"
Add Jean Gallier's Differential Calculus book
Add Bill Hails' Perl book
Add three Python books
Add Django book
Add "Data Mining with R"
Add Snort book
Merge pull request #332 from tml/master

Share my local updates back to the upstream