Color Output

It would be nice to have a library for doing color output.

This could be used by dylan-compiler as well as testworks for highlighting errors, warnings and other relevant information.

It should be aware of whether or not the output stream is a tty (on Unix, this can be determined by isatty) and disable color output on non-terminal outputs.

It should be able to check the TERM type and customize the output according or make additional features available.

Some of the code in https://github.com/iglennrogers/dylan-ansi.git may be useful.