Add EDA_BASE_FRAME::Show() and call SaveSettings() only from there for all derived wxFrames.  Remove calls to SaveSettings() elsewhere.

Pcbnew: fix bug #1272714 . Code cleanup: use 2 different enums for pad shapes and pad drill shapes. Remove never used pad shape.

https://lists.launchpad.net/kicad-developers/msg11965.html

Switch to boost::context for all platforms, almost.
Please try your platform by commenting out fcontext.s in common/CMakeLists.txt.

Move HitTestForCorner and HitTestForEdge code from class_zone to polygon/PolyLine.cpp, to avoid redundant code.
Fix bug 1264248.
Fix a very minor issue in RemoveTrailingZeros, for countries where the separator in floating numbers is a comma.

Pcbnew:, libedit, Save lib as...: the new .pretty lib format is the default, instead of legacy .mod format. The legacy format is still selectable in the file selection dialog.

   To use multiple working threads.  This entailed adding KiCad typedefs:
*) Add typedefs for MUTEX and MUTLOCK which mask the actual choices for the project.
*) Add FOOTPRINT_LIST::DisplayErrors( wxWindow* ) which is a single strategy for
   showing aggregated load errors.  Although what's there is only scaffolding
   and needs a volunteer who knows HTML pretty well.
*) Ensure all callers of ReadFootprintFiles() use the new DisplayErrors() function.   
*) Push utf8.cpp and utf8.h into common library for open use.

* Make the tool bar dockable.
* Enable the overflow control in the tool bar in case the it does not fit in
  it's parent window.
* Fix some wxAuiPaneInfo usage issues.
* Remove unused wxAuiPaneInfo objects.
* Move perspective saving and loading into EDA_BASE_FRAME object in preparation
  for extending this to all frame windows.