Output when running an app Dart command line launch in the editor should handle escape sequence for Linux shell colors.

See http://linuxshellaccount.blogspot.com/2008/03/using-color-in-linux-or-unix-shell.html

for example:

    String GREEN_COLOR = '\u001b[32m';
    String NO_COLOR = '\u001b[0m';
    print("Parsed ${GREEN_COLOR}main.html${NO_COLOR}in 23 msec.");

Would display the text in a Linux shell as:

             Parsed main.html in 23 msec.

where "main.html" would be green and the rest of the text is black.

Nice so that rich tools that return errors in red, warnings in yellow, etc. can be written to look nice in the editor's Command Line window. Instead of looking:

� Parsed [32mmain.html�[0m in 23 msec.