Fixed: render sorting issues with multiple translucent 3D floors next to each other on different heights

Fixed: the model should be Z-scaled to 0.83 even in unstretched view to ensure that models fit the geometry right (reported by Ozymandias81)

Fixed: texture copy/paste in the visual mode was detected as failed pasting and caused a beep. (reported by DOOMGABR, abbuw, Turret_Master)

Fixed: the old way of checking for GZDB's directory writability would not work in certain versions of WINE/Mono

Fixed: cutting a thing in visual mode would leave disposed BaseVisualThings in the selection. (reported by DOOMGABR)

Made Skulltag item sprites optional to support default Skulltag+Zandronum config without producing 100 errors

Fixed state lookup logic for sprite guessing; it should always prefer SPRITE_CHECK_STATES to using the random first frame.

Fixed: duration 0 frames should be skipped if there are nonzero frames after them (reported by Tormentor667, Ozymandias81). Fixed crash if some actor had a modeldef entry but doesn't anymore.

Fixed: inheritance from game configuration for dynamic lights; Fixed: visual representation of inherited lights (reported by Nash); Fixed: inherited thing arguments from game configuration; Added: //$ClearArgs for clearing inherited arguments.

Fixed: sprite replacements with different rotation count weren't handled correctly. (reported by DOOMGABR)