Fixed, Map Analysis mode: fixed a crash when trying to dissolve an invalid sector when one of it's linedefs referenced it on the both sides.
Fixed, Sectors mode: fixed incorrect undo description when deleting sectors.
Internal: joined declaration and assignment of some more variables.
Nodes Viewer mode: added more boilerplate to classic nodes reader.
Thing Filters Form: program configuration was not marked as changed when saving thing filters.
Cosmetic layout fixes in Thing/Linedef/Sector Info panels.
Cosmetic text fixes in several Map Analysis results.
Internal: debug console is now cleared when creating a new map.
Updated ZDoom_DECORATE.cfg.
Fixed, Nodes Viewer Mode: the mode was unable to handle missing node lumps properly.
Fixed, Nodes Viewer Mode: the mode no longer builds nodes when unable to find both classic nodes and ZNODES at the same time.
Removed SlimDX installer, because it's no longer required.
Internal: debug console is now cleared when opening a map.
Fixed, Texture Browser Form: well, I broke "Tab" key functionality again (in previous commit)...
Maintenance: changed curly braces style to match DB2 one (hopefully not breaking anything in the process...).
Maintenance: changed private method names casing to match DB2 one.
