Rechargable Batteries

Basically just adds the rechargable flag to small and medium storage batteries.

Considered adding the flag to 'storage battery' item but there is a quick and easy way to recharge those already in CDDA, 'swappable storage battery case' and that doesn't impose the energy inefficiency of using the 'UPS-compatible recharging station' or 'battery charger' (Bright Lights mod).

Basically every charge of energy imparted by the recharge mechanism costs you 10 units of energy from the vehicle.