tests to avoid regressions

[kthakore]

interesting tests coming to mind:

• test with a couple of exotic languages including arabic (my mail includes a pointer to a change from kartik probably breaking proper arabic behaviour in chat)
• all game types (regular 1P, 2P, MP training, LAN, and NET play)
• game recording and replaying
• game pausing (keyboard Pause key)
• starting the game without a sound device attached (used to be a recurrent process blocker with some versions of SDL or/ sound libraries)
• highscores in multiple combinations (regular game, MP training)
• more and more tests in more weird cases!