[GAMEPLAY] Tournament winnings do not match the original

[mrannanj]

The tournament winnings formula is not based on what the original does, but it is a self made guess that only works decent enough on the North American tournament, but otherwise gives the player too much money.

Now, we have ways to find out what the original bases winnings on, so that should be implemented here. In the original, winnings are based on what the enemy robot is worth and maybe if the pilot has money. OpenOMF does not implement enemy pilots using their money at the moment, so first step there would be to make enemies spend their money on upgrades, using some bogus formula.

Once we have enemies spending their money, need to look into how exactly their net worth is calculated and how it affects the player winnings.