gr_basic.cpp: fix a bug I created in my last commit. Pcbnew: fix a very minor bug in hight light behavior

* Change class WinEDA_MsgPanel name to EDA_MSG_PANEL per coding policy.
* Change some old set message panel code in PCBNew with updated message
  panel methods in EDA_DRAW_FRAME.
* Remove unused global function Affiche_1_Parametre.
* Minor Doxygen warning fixes.

In Render, colors shown were the default colors, not the selected colors, when starting Pcbnew or Gerbview,
because colors were not updated after reading the config.

All: fix a very minor issue: when a window is closed mazimized, and later reopened, it was not maximized.

fix an issue created by commit 2954. Gerbview: display now an indicator of layers in use. minor code cleanup.

* Move undo item copy global variable into schematic editor frame object
  member variable.
* Add helper methods for accessing the undo item copy member variable.
* Fix undetected bug when changing a text type.
* Added an exchange command to the undo/redo base class for handling undoing
  a changed item type which cannot be undone by swapping out the variables.
* Revert change to common/hotkeys_basic.cpp that broke hot key behavior.
* Lots of coding policy changes while making the changes above.

* Gerbview, Pcbnew: add SetLocaleTo_Default() after reading double in config to fix issues with decimal separator (when the separator is not a point).
(WxWidgets 2.9.1 seems call setlocale( LC_NUMERIC, "" ) when wxConfig read doubles stored in config, but forget to back to current locale.)
Note: perhaps there are some dialogs that need this call to  SetLocaleTo_Default() ).
* Minor  code cleanup in pcbnew/netlist.cpp

* Rename EDA_Rect class to EDA_RECT.
* Rename EDA_TextStruct class to EDA_TEXT.
* Remove duplicate Doxygen comments from sch_sheet_path.cpp.

* Fix about dialog escape key termination bug.
* Fix edit hot keys dialog escape key termination bug.
* Set schematic editor component properties dialog default button.
* Fix schematic editor plot DXF dialog escape key termination bug.
* Set PCB editor layers setup dialog default button.
* Set PCB editor swap layers dialog default button.
* Set PCB editor net list dialog default button.
* Add comment to UIPolicy.txt about escape key termination requiring proper
  dialog button IDs.

* Set default button on all dialogs that do not already have a defined
  default button.  The only exception is the EESchema net list dialog
  which needs converted over to wxFormBuilder and due to it's design makes
  setting the default button in any tab other than the default tab
  problematic.
* Fix escape key dialog handling bug in EESchema print post script
  dialog.

others: fix minor issues.

* Remove clearance and net class name read only text boxes from PCBNew
  auxiliary tool bar.
* Display full net class information in message panel when an object that
  supports net classes is selected.
* Move coordinate string conversion function to EDA_DRAW_FRAME object and
  made it more versatile.
* Refresh message panel text when units change.

Pcbnew: dialog plot: make message window resizable, add tool tip and remove unused sizers.

All: fix a minor bur annoying issue: incorrect cursor shape after a block command (mainly when a tool is selected)

Pcbnew: Fix a very minor issue in left toolbar. Add option in dialog bloc to move,copy ... items on invisible layers or not.