Fix a bug that crashes Pcbnew when closing Freeroute dialog ( Only happens with wxWidgets 2.9.1, but this was a bug)

pcbnew and directs gerber/hpgl etc. output into that directory.
There's a browse button that opens a dialog for browsing. If the
directory does not exist, it is created. Tested in linux, not in
windows. Wxwidgets methods are used for file (name) manipulations, so
things are probably ok in windows, too.

marco

Pcbnew: minor code cleanup and enhancement in zone filling. Commit patch from Marco Mattila. Eeschema: minor bug fix about dangling ends. removed obsolete file

Pcbnew: fix a serious bug in ZONE_CONTAINER::HitTestFilledArea( ) which could break connectivity calculations relative to copper areas.
Fix also very minor issues relative to copper zones.
Update boost::polygon from Boost svn repository.

Eeschema: fix bug in load_one_schematic_file.cpp: error about files version, that create errors for hierarchical labels.
Pcbnew: cleaning code in block.cpp, and modifye previous way to calculate block size in block command, because old way creates unexpected behavior in block rotate and block flip.
Pcbnew: Fix a bug in plot silkscreen layers.
Cvpcb: Fix compilation issue under MACOX

can be deleted later if they exist in the headers, or moved to 
headers if they should exist in the headers.