add 'The well grounded Rubyist'

[anhhct]

One of the most recommended books for learning Ruby. Things are presented in a comfortable pace, not too fast but not wasting time into unnecessary details. Like being said in the book's title, it gives you the information you need to become well-grounded in Ruby, which means not only the syntax but also thinking the Ruby's way, writing the Ruby's way and also using the tools given along with Ruby's binary release. Even though the book was written some time ago and only cover Ruby 1.9, it's still recommended by many Rubyists and still applicable at the moment.

[runlevel5]

I've never heard about this before, but after looking into the TOC, this books seems very good in fact 👍