Update from KeldorKatarn branch

This approximately corresponds to 971ba4928a5c7c7916fea55d91a3b6dd5bba140c,
excluding the different virtual train build GUI, but including the basic
changes to the original train build GUI for multiplayer to work.

Fixup

src/vehicle.cpp

@@ -1032,9 +1032,7 @@ void CallVehicleTicks()
 		bool stayInDepot = it->second;
 
 		it->first->vehstatus |= VS_STOPPED;
-		CmdTemplateReplaceVehicle(t, stayInDepot, DC_EXEC);
-		/* Redraw main gui for changed statistics */
-		SetWindowClassesDirty(WC_TEMPLATEGUI_MAIN);
+		DoCommand(t->tile, t->index, stayInDepot ? 1 : 0, DC_EXEC, CMD_TEMPLATE_REPLACE_VEHICLE);
 	}
 	tmpl_cur_company.Restore();
 }