New Malf Power: Override Machine

* Added a new malf power: Machine Override will delete the machine and swap it with a mimic, with generated attack stats and the same icon as the machine it has replaced. Effectively making it look like the machine is attacking people.
* The power will cost the same as overload.
* Reduced the price and uses of uncommon malf powers so that they can be used when the AI only has 5-10 points left.