Cosmetic changes in Sector Info Panel and Thing Browser Control.
ArgumentInfo: fixed a crash when enum specified in a game configuration doesn't exist.
Updated Hexen and ZDoom linedef configs.
Updated ZDoom_DECORATE.cfg
Open Map in Current WAD: resources are now reloaded when current and target map's resources don't match.
Added some boilerplate to UniversalParser and PK3FileImage.
Internal: ImageSelectorControl now has "UsePreviews" property.
Internal: added ConfigurablePictureBox.
Updated ZDoom_DECORATE.cfg.
Visual mode: "Lower/Raise Floor/Ceiling" actions now work on surfaces with sector slopes.
Cosmetic: numeric textboxes, which support relative values, now have differently colored text and a tooltip.
Internal: renamed Sector.CeilingSlopeOffset to Sector.CeilSlopeOffset, Sector.CeilingSlope to Sector.CeilSlope to match their names with similar sector properties.