Fix most of the warnings in the Visual Studio build

- Fix energy-draining weapons
- Specials called when a spell is targeted on a space now work a little differently if the spell is multi-target. For each target, the special is triggered if it exists; otherwise the normal spell behaviour occurs.

src/pcedit/pc.editors.cpp

@@ -240,7 +240,7 @@ void display_alchemy(bool allowEdit) {
 		if(!allowEdit)
 			showAlch->getControl(id).attachClickHandler(&cLed::noAction);
 		cLed& led = dynamic_cast<cLed&>(showAlch->getControl(id));
-		if(univ.party.alchemy[i] > 0)
+		if(univ.party.alchemy[i])
 			led.setState(led_red);
 		else led.setState(led_off);
 	}