My Project Euler Work

Solved!
* 1 2011.09.22 - `ruby src/1.rb`
* 2 2011.09.22 - `ruby src/2.rb`
* 3 2011.09.22 - `ruby src/3.rb` (and _much_ faster `ruby src/3.lib.rb` that uses a library to generate primes)
* 4 2011.09.22 - `ruby src/4.rb`
* 5 2011.09.22 - `ruby src/5.rb`
* 6 2013.01.02 - `ruby src/6.rb`