* Make USE_WX_ZOOM clipping routine actually clip rather than just test
if line needs drawn.
* Clean up as many USE_WX_ZOOM #ifdefs as possible.
* Minor coordinate rounding improvements.
* Minor scrolling and panning improvements.
* Remove unused KicadGraphicContext object code.
* Implement code to allow wxDC to handle coordinate conversions between
device and drawing units.
* Add build settings to enable wxGCDC for wxGraphicsContext testing.
* Remove wxAUI conditional build cruft as it is now required to build
Kicad.
* Fix scroll increment size regression to prevent jumping around the
zoom center position.
* Add find GDI+ cmake module for building on WXMSW when wxGraphicsContext
is enabled.
* Create single event handler for grid size events.
* Fix all frame windows to use new grid size event handler.
* Use offset relative to ID instead of ComboBox index to save last grid size.
* Move last grid size load/save setting into WinEDA_DrawFrame.
* Add equality and assignment operators the GRID_TYPE.
* Add current grid helper methods to BASE_SCREEN.
* Add GetPins helper to LIB_COMPONENT to replace GetNextPin where applicable.
* Add AppendMsgPanel helper to WinEDA_DrawFrame.
* Improve rounding for display of coordinates when millimeter units are selected.
* 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.