Added a colored outputter to embUnit.

The outputter is called ColorTextOutputter and can be enabled by defining OUTPUT=COLORTEXT.
The colored outputter behaves just like the TextOutputter, but displays successful tests in GREEN and failed tests in RED. The summary message is also in GREEN/RED, but is slightly different from the TextOutputter.

Also:
* Added fancy simple none-verbose color-outputter for EmbUnit. The outputter outputs a simple statistics line in GREEN or RED, according to the test success or failure. (Also, the ColorTextOutputter was adjusted to use the statistics output of this new ColorOutputter.) The new outputter can be activated with OUTPUT=COLOR.
* Added a single character "." output for the simple color outputter and replaced the color codes by macros.