fixed bug 641982 (I hope)

removed in drawpanel an erroneous change (was made only for a test). drc code cleaning. cmakelist.txt changes in minizip.

Added boost::polygon (experimental)
Added experimental zone fill calculations with boost::polygon
Added patches from Yury Khalyavin

Fixed compil warning under wxWidgets 2.9.1.
File beautification
Statring using wxTextEntryDialog instead of Get_Message (because Get_Message does not handle properly cancel option)

fixed bug 603481. Better bitmap2component look. fixed some locate problems for footprints using polygons (mainly created by bitmap2component)

* Fix a minor problem with wxFileDialog to open a file that no longer
  exists in PCBNew.
* Make GerbView open file behavior the same as PCBNew.
* Remove redundant PCB file wild card definition.
* Add open file refactor task to the todo list.
* Fix some minor code formatting issues.

This patch applies on the very last svn  (r2402) and removes all
disfunctionnal python code (including deletion of unused strings)

* Changed line clipping function in gr_basic.cpp when USE_WX_ZOOM is
  enabled.
* Set wxDC clipping region to client size when drawing outside of paint
  event handler.
* Updated kicad and eeschema CMake files as the common library now
  requires linking to the polygon library.

* 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.

Added patch for macOSX
turn on fast algo for draw grid (should work now)

* Fix debug asserts when passing NULL pointers to wxAuiPaneInfo.
* Fix Kicad main window sash sizer bug when using wxAui.
* Remove specctra_test from Visual Studio builds to prevent build errors.
* Add WIN32 to layer widget test so it will build properly on Visual Studio.
* Fixed compiler conversion warnings in PCBNew.
* Fixed worksheet print scaling in PCBNew.
* Minor code renaming.