Finnish Sirens & Equipment 1.1

This update brings a new siren to the pack, a old Finnish police siren. Also included is the new Integrated Lighting System roofbox very commonly seen in Finland and other countries close to Finland, such as Estonia and Sweden (I kind of wish that modders from these countries are interested in this, I'd be happy to see them use this)!

The roofbox is far from perfect, but since GTA 6 and Euro Truck Simulator 2's Coaches DLC is coming out, I probably won't have time to work on it more before...