1.7 bug with ZIS truck

Copy from change log :

* Removed Mustering Tent requirement from ZiS-5 Medic Truck

I played a skirmish game and start with T2 , but it dont allow me to build Medic Truck until I build T1.

well, I'm fine with that, it's really not that worth to heal 1, 2 snipers or a bunch of stupid ingenery.