Add methods to convert between a hex string and byte array.
Add a Queue.empty property.
Replace the numerous predefined colors with those from http://clrs.cc/

- The main use for predefined colors is placeholders during development.
  It isn't important enough to spend too many lines of code on.
- The new colors look better.
- Why wade through a huge list of named colors when you can use any
  custom color by specifying the RGB values?