[FIXED] Dealerships OP when continually subsidized

[StephenClark]

Subsidizing dealerships repeatedly results in extremely high bonuses to buyer rating. In the attached saved game, look at New York and see 40,000 bonus to buyer rating from dealerships in 1977.

Actually, in this game, I wasn't checking consistently to see when the subsidize option came off cooldown. If I had checked it every turn it could have been even higher.

Dropbox link below as file is too large. 

https://www.dropbox.com/scl/fi/bky95c784...jknxj&dl=0

[Eric.B]

I've decreased the effect of the dealership subsidy just slightly. But more importantly, the AI is now using this system automatically. That should negate this bonus somewhat.

Changes will be in v2.4.0.1 and v.2.0.0.13 (or 14, I forget what number we're on with Regular GC.)