Add a workaround to fix a new bug in wxWidgets 3.0 ( Windows specific ) which shows icons only with a size = 16x16 in menus which have attribute wxITEM_CHECK

Fix some incorrect icons (which were using a not supported font for texts). Add ps_router icon from Konstantin Baranovskiy.

Add missing calls to Show( false ) to some main frames (Kicad, eeschema, gerbview), to force config saving when closing these windows.
Code cleanup and minor coding style fixes  in footprint_wizard_frame

*) Enhancements to make_lexer().
*) Support multi-threaded build.
*) Switch to "bzr patch" from patch.exe for Windows users.

* Add third list control with library names.
* Add button to toolbar to select filter by library name.
* Add bitmap for filter by library name toolbar button.
* Remove custom UI colors from list controls.

Eeschema: fix broken  mirroring for texts and labels in block mirror X and Y (this fixes Bug #1135505)
Pcbnew: add in module popup menu an option to edit the footprint in Modedit (like in Eeschema for components)
minor icons enhancements.

Because now there are 2 formats, board backup files extensions are .brd-bak or .kicad_pcb-bak instead of the old .000 extension, depending on the initial file format.

Also a minor cosmetic enhancement

Kicad manager: shows now svg files in tree files.
Pcbnew: fix incorrect printing (board out of page) when creating drill map in postscript format ( noticeable mainly for small boards)

  *  serious code cleanup (remove duplicate code)
  *  shows (option in 3D preference menu) the copper items (tracks, zones...)  in 3D, using 35 microns copper thickness.
      However, because there are a lot more3D data to show (roughly 4 times more), this is slower.

This is *a work in progress*, so some features are missing, and/or could be modified.
Mainly keepout zones are not yet exported to autorouters, and pads are not taken in account.
Some code cleanup in polygon.*

* Footprint wizard C++ generic classes
* Footprint wizard C++ to python wrappers 
* Automatic plugin loader from ~/.kicad/plugins
* Python plugin architecture: Footprint wizards

Should allow Pcbnew code easier to change and Gerbview code more understandable and easier to maintain.
Code cleaning (remove dead code, add comments).
Minor other enhancements.

Remove 2 duplicate icons.
Minor cosmetic enhancements and fixes in popup menus.

Eeschema: fix a bug in bool SCH_LINE::MergeOverlap( SCH_LINE* aLine ): ends point of resulting segment incorrects.
remove unused icon files.

Pcbnew:
 * graphic_item_properties_base.fbp * dialog pad edit: make some strings more easier to translate.
 * global pad edition: fix a bug that change pad position instead of pad size (round pas only).
Eeschema:
 * fix a bug: new created wires were not alwaes shows until the screen was redrawn.

Icons for modedit and modview: remove unused or duplicate icons files and rename files. Tweak some icons.

Minor cosmetic enhancements.
Pcbnew: more workd abput connection algorithms (work in progress)

Pcbnew: prepare work on new algos for connections calculations.

Eeschema, Libedit: Use 16x16 icons in comboboxes inside the pin editor dialog. This gives a better look to this dialog.

Fix compatibility issues with old xpm icons.
Add or update .xpm and .ico files for shortcuts and taskbars
Remove artwork folder.

* Replace use of wxICON by new icons declaration.
* Remove unused files.
* Fix filenames inconsistencies between old and new icons.
* dialog_erc handle variable size icons in erc matrix.

* Added checks for Inkscape and pngcrush when MAINTAIN_PNG mode is enabled.
* Rebuild PNGs with transparent background.