Add icons to background themes; allow to hide themes explicitly by adding “hidden” key to theme.cfg
sky = 0, 0, 0
border = 106, 106, 106
music = EarthRise.ogg
clouds = 0
object = Rock, 3, 65, 258, 175, 2, 1, 0, 0, 240, 215
object = RockShort, 3, 0, 165, 163, 2, 1, 0, 0, 163, 140
flakes = 20, 1, 0, 20, 0
sd-tint = $ff, $ff, $ff, $ff