EAGLE_PLUGIN now establishes (trace_min), (via_min_size), (via_min_drill), and Default Net's (clearance)
by groking the eagle *.brd info.  This makes it more probable that fewer DRC errors come about on first 
DRC attempt.

* Encapsulate most of the MODULE class.
* Start encapsulating the DIMENSION class.
* Lay some groundwork for EDA_TEXT encapsulation.
* Move cleverly hidden MODULE functions into class_module.cpp.
* Use std::swap to exchange TEXTE_PCB values for undo/redo.
* Remove unused members from MODULE class.
* The usual coding policy and documentation fixes.

Reverted back the ( i ) parameters for python, applied the PyGILState_Ensure from Dick into his PyLOCK class

improvements to python's GIL acquisition and release, but not done yet, since I think the GIL needs to be acquired even when not involving wxPython.

Pcbnew: fix issues:   Ensure pads type connector  have a drill size= 0, like SMD pads. Ensure keepout zones have no net.

Pcbnew: Partial merge from pcad2kicad (from Alexander Lunev). Fix an old bug related to pads with offset: sometimes the connection to a zone was not detected.

* Fix all Doxygen warnings except polygon files.
* Add footprint library table tasks to TODO.txt.
* Add definition to drag.h to prevent nesting.
* Coding policy fixes.

Pcbnew: fix Bug #1148785 (pcbnew crashes when using only one layer in autorouter ) , and a minor bug in dialog cleanup.

Still fix minor issues in dialog_edit_module_for_BoardEditor.cpp (noticeable only for non English users)

* Fix spacing and consistency issues and debug warning due to improper flex
  grid sizer in module editor module properties dialog.
* Fix spacing and consistency issues in Pcbnew module properties dialog.
* Fix spelling error in DRC dialog message box text.

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.

CMakeLists.txt: use elseif token instead of elif which create strange issues with some cmake versions.
Fix minor issues in nsis config files

Fix minor issues in nsis config files