Add Upgrade support to Power/CanPowerDown

Another piece for adding DeploysToUpgrade and hopefully fixing WithMakeAnimation.
Requires #6750.

With UpgradeActorsNear, it can be used to require a deployed Construction Yard near by in order to power down. Limiting power would require also using traits like DisableUpgrade.

Will be used for TS GDI power turbines.

It would be clearer to store the PowerManager directly, although you will then need to update that on ownership change (compare with StoresResources).