Create libcdr.rb

This formula is still incomplete.
Just wanting to see if it passes brewbot test. 
Reference issue: https://github.com/Homebrew/homebrew/issues/30383
I tried and I'm not proficient enough to know how to do that. Here is the beginning of my attempt: https://gist.github.com/luzpaz/de7ed3b40bbdab7a9873 but I got overwhelmed looking for a function and using the correct library