* Remove clearance and net class name read only text boxes from PCBNew
auxiliary tool bar.
* Display full net class information in message panel when an object that
supports net classes is selected.
* Move coordinate string conversion function to EDA_DRAW_FRAME object and
made it more versatile.
* Refresh message panel text when units change.
* 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.
* Old control state handling code completely removed in all applications.
* Factor common control state handlers into EDA_DRAW_FRAME.
* Replaced EDA_ITEM test for newness with IsNew() method.
* Factor vertical right toolbar command handlers out of giant edit command
switch statement in EESchema and PCBNew.
* PCBNew remembers last net list read during the current editing session
as well as between project editing sessions. Closes bug 576902.
* Separate PCBNew application settings from project file settings and
allocate them dynamically instead of statically to make it easier to
eliminate global variables.
* Split out application specific command IDs to prevent unnecessary rebuilding.
* Eliminate duplicate menu and tool bar command IDs.
* Split component library editor and viewer definitions to separate header files.
* More component library and document file merge code.
* A bunch of minor string readability and consistency fixes.