Made some float/int/unsigned char conversions explicit, fixed ParticleSystem:getColors, fixed love.mouse.isDown with x1 and x2 buttons

src/modules/mouse/Mouse.h

@@ -42,10 +42,10 @@ public:
 		BUTTON_LEFT,
 		BUTTON_MIDDLE,
 		BUTTON_RIGHT,
-		BUTTON_WHEELUP,
-		BUTTON_WHEELDOWN,
 		BUTTON_X1,
 		BUTTON_X2,
+		BUTTON_WHEELUP,
+		BUTTON_WHEELDOWN,
 		BUTTON_MAX_ENUM
 	};