Add support for the --no-color option.

The `colored` gem was replaced with `colorize`. It has a very
similar API but comes with a few extra methods to remove or check
colors.

The Tabber class has had an options hash added to it, to make
further additions easier.
Test that omitting the no_color option will allow colors to be printed.
Merge pull request #32 from samsymons/no-color

Add support for the --no-color option.