scroll slider contrast

fix scrollbar, minimap slider transparencies

dark: "minimapSlider.activeBackground": "#ffffff40", "minimapSlider.background": "#ffffff20", "minimapSlider.hoverBackground": "#ffffff60",

	"scrollbarSlider.activeBackground": "#ffffff40",
	"scrollbarSlider.background": "#ffffff20",
	"scrollbarSlider.hoverBackground": "#ffffff60",