Stop gcc with -Wswitch complaining about missing NONE

Include/Rocket/Core/Variant.inl

@@ -81,6 +81,10 @@ bool Variant::GetInto(T& value) const
 		case VOIDPTR:
 			return TypeConverter< void*, T >::Convert((void*)data, value);
 		break;
+
+		case NONE:
+		break;
+
 	}
 
 	return false;