Invalid strategy bullet proofing

[m09]

Test every case: bad methods, corruption during execution, bad directions, bad positions for the robot, etc and react accordingly (most likely a map reload + warning dialog)

[daimrod]

Whenever we found a bug in the error handling, we need a minimal script to reproduce the error with a complete description (what was expected, what happens) and put it in test/python/.

I'll write something to integrate them in the tests suite.