* Eliminate external direct manipulation of component draw item pointer.
* Add draw item remove, add, and locate methods to library component object.
* Remove redundant locate pin, field, and draw item code.
* Fix add new pin drawing bug that left initial pin draw in place.
* Improved best zoom calculations for small components.
* Library component bounding box calculation now includes fields.
* Removed unnecessary header file "libcmp.h".
* Fixed potential locate draw item bug in library editor hot key handler.

* Component library objects renamed for improved readability.
* Fields now move when selected in library editor.
* Add copy constructor to all library draw and library component objects.
* Added copy constructor to EDA_BaseStruct.
* Delete base screen in WinEDA_DrawFrame destructor to prevent potential memory leak.
* Fixed memory access bug when replacing and adding a component to library.
* Moved library component block manipulation code into component object.
* Removed all of the global variables used by the library editor main window object.
* The usual code cleaning and refactoring.

* 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.

* Create static component library methods to manage library list.
* Rename component library, component, and alias objects to more readable name.
* Use pointer to component instead of root name to prevent redundant library searches.
* Add append message helper to message panel that calculates string length.
* Initial ground work for merging library and library document files.
* Improved component library file load error checking.
* Minor component library editor improvements.

* Add offset and block hit testing to library component objects.
* Improved search for library entries.
* Fixed library component editor component removal and addition.
* Library editor now uses wxUpdateUIEvents for updating all UI objects.
* Added version check to cmake find boost macro.
* Removed unused code in file libalias.cpp.
* Added method to WinEDA_DrawPanel to take mouse out of managed mode.

* Replaced WinEDAListBox buttons with wxStdDialogButtonSizer.
* Moved library draw entries GenCopy method to base class.
* Remove priorque.cpp and priorque.h from CMakeLists.txt.
* The usual code cleaning and uncrustification.

fixed: incorrect sub path calculation for libs and doc filenames (full filenames where always converted to relative paths,
even when they are not in standard libraries paths)

pcbnew: remove old of two To_User_Unit(), redraw ratsnest on/off, magnetic cursor to start move/drag module

pcbnew: Starting work on undo/redo in pcbnew. Only some delete item commands are stored in undo/redo stack

Rework on undo/redo and block functions: more efficient code to undo/redo block move and mirror operations

Rework on undo/redo and block functions: more efficient code to undo/redo block move and mirror operations