* Handle different item global deletions correctly. No more removing of text
if graphics is selected.
* Layer settings are always obeyed for modules, zones, text, and graphics.
* Text will be removed from copper layers if all layers are selected or
according to the current layer.
* Added check boxes for "normal" and "locked" footprints to be consistent
with the naming for the track deletion options.
* Fix grid select box update bug on context menu.
* Fix via size and track width select box update bugs.
* Fix layer pair indicator button update bug.
* Fix auto track width tool bar control enable bug.
* Fix via size and track width select status bug in context menu.
* Fix layer select box and layer control widget select bug when current
layer is removed.
* Add virtual function to notify objects derived from EDA_DRAW_FRAME that
the units setting has changed.
* Coding policy class naming fixes.