Abscissa test: option to turn off colored output in tests

[greg-szabo]

I'm doing testing using the Abscissa framework.

The output of stdout is color-coded on my local machine, but not-colored on CI. Instead of changing the dev environment (and forcing all developers to do the same) to get non-color-coded output, I would like to have an option in the Abscissa test framework that tells the application to run on a non-color terminal.

If I ran the application manually, I would be able to set an environment variable to tell the application that the terminal doesn't support colors. I guess that could be an option in the tests too.