Addition of an alternative to "invisibles" that can actually play - just a configuration addition

[rvilling]

My understanding of the test team "invisibles" is that it doesn't correspond to any SPL team number and is safe to use for any test games. My understanding is also that you cannot configure robots to play as "invisibles" (but perhaps that understanding is mistaken).

For certain kinds of tests at RoboCup it would be useful to be able to configure an opponent team that does not correspond to any SPL team. For example if one team wants to test a penalty shootout without involving any other teams they could do it if there was a second generic team on the Game Controller.

In our lab, we configure a second generic team as "Benchwarmers" and give it an unused team number. Would it be possible to do this more officially so that the feature is available at RoboCup competitions also and ensure support in both the Game Controller and TCM?