Charras beat me on fixing the include/sch_item_struct.h include issue from 4069

All: change some texts and messages hard to translate, or not translatable (and some incorrect messages).
Pcbnew, layer manager: add option (popup menu) to always keep copper layers not visible but the active layer, even when the active layer is changed.
Usefull for multilayer ( more than 4 layers) PCBs.

In particular the new mechanism for handling extended color palettes is in place,
included renaming the ini keys and saving the color name instead of its index; this means better forward compatibility with palette changes.

Since ini keys are changed, colors will be reset

Implemented the LAYER_NUM typedef (LAYER was already taken as a class name...) to represent a layer number.

* Complete encapsulation of the ZONE_CONTAINER class.
* Fixed a bug in the EDA_TEXT::Format() default effects behavior due to
  improper conversion to internal units and missing test for default
  thickness.
* Improved grammar of some Pcbnew context menu strings.
* Moved some more cleverly hidden BOARD object methods into class_board.cpp.
* Lots of coding policy and documentation fixes.

* Complete encapsulation of the MODULE class.
* Complete encapsulation of the EDA_TEXT class.
* Encapsulate most of the ZONE_CONTAINER class.
* Add pcbcommon library as a dependency for reSWIGging the scripting
  support.  This should cover most dependency cases.

* 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.

3D viewer: allows  import of models created with openscad and convertedvia meshconv to wrl (thanks to Georg Gast <georg@schorsch-tech.de>)
Export VRML: fix scaling issue for pcbnew - nanometers.

Pcbnew: fix an issue when collecting vias (for instance when left clicking on a via, it was not always detected)
This bug was mainly noticeable when using buried vias (some were never detected)
Minor other fixes (typos, strings hard to translate ...)

switch all <math.h> includes to <cmath> includes on an attempt to dodge some abiguous references to atan2()

All: fix some Doxygen warnings

Code cleaning, minor fixes and minor coding style fixes. wxWidgets 2.9.4 compatibility fix( deprecated function MakeModal )

Pcbnew: drag functions: serious cleanup and better code. Use now the connectivity functions to find tracks connected to pads,
and therefore  tracks are now dragged when a end point is inside a pad, not necessary on the pad position.
However, drag functions still need more cleanup.

  *  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.

3d-viewer and polygon functions: remove duplicate code about conversion from basic shapes to polygons.

Eeschema: annotate and netlist dialogs: enhancements.
Minor  coding policy fixes and  changes.

All: press ctrl+shift key when moving the mouse allows the graphic cursor to be moved outside the grid.
(useful to place graphic objects, texts in any position, regardless the current grid)

Some coding style policy fix.

* Add s-expression file parser object and keyword files.
* Fix minor issues with s-expression file formatting.
* Fix a minor bug the zone container fill state parsing in the legacy plugin.
* Move EDA_TEXT visibility definition to eda_text.h.
* Add minor BOARD_ITEM object improvements to support s-expression file
  parser.

3D viewer: fix incorrect scaling factor when using nanometers.
Very minor other fixes

// This provides better project control over rounding to int from double
// than wxRound() did.  This scheme provides better logging in Debug builds
// and it provides for compile time calculation of constants.


#include <stdio.h>
#include <assert.h>
#include <limits.h>

//-----<KiROUND KIT>------------------------------------------------------------

/**
 * KiROUND
 * rounds a floating point number to an int using
 * "round halfway cases away from zero".
 * In Debug build an assert fires if will not fit into an int.
 */

#if defined( DEBUG )

// DEBUG: a macro to capture line and file, then calls this inline

static inline int KiRound( double v, int line, const char* filename )
{
    v = v < 0 ? v - 0.5 : v + 0.5;
    if( v > INT_MAX + 0.5 )
    {
        printf( "%s: in file %s on line %d, val: %.16g too ' > 0 ' for int\n", __FUNCTION__, filename, line, v );
    }
    else if( v < INT_MIN - 0.5 )
    {
        printf( "%s: in file %s on line %d, val: %.16g too ' < 0 ' for int\n", __FUNCTION__, filename, line, v );
    }
    return int( v );
}

#define KiROUND( v )    KiRound( v, __LINE__, __FILE__ )

#else

// RELEASE: a macro so compile can pre-compute constants.

#define KiROUND( v )  int( (v) < 0 ? (v) - 0.5 : (v) + 0.5 )

#endif


//-----</KiROUND KIT>-----------------------------------------------------------

// Only a macro is compile time calculated, an inline function causes a static constructor
// in a situation like this.
// Therefore the Release build is best done with a MACRO not an inline function.
int Computed = KiROUND( 14.3 * 8 );


int main( int argc, char** argv )
{
    for( double d = double(INT_MAX)-1;  d < double(INT_MAX)+8;  d += 2.0 )
    {
        int i = KiROUND( d );

        printf( "t: %d  %.16g\n", i, d );
    }

    return 0;
}

Enhancements in AddMenuItem (that accepts now a menu type)
Partial use of the Edwin van den Oetelaar's patch (patch not fully working or correct)

* BLOCK_SELECTOR class is not longer derived from EDA_ITEM.
* Encapsulate BLOCK_SELECTOR class member variables and add access methods.
* Move HandleBlockBegin() function from block_commande.cpp to drawframe.cpp.
* Remove virtual methods from top level derived objects per future
  coding policy change.
* Remove Doxygen copydoc statement from objects derived from EDA_ITEM
  since the comments are automatically copied to the derived object.
* Removed copy and pasted Doxygen comments from objects derived from
  EDA_ITEM.

ModEdit (and ModView): make "invisible" texts visible. They are not visible in  the board editor, but must be visible in the footprint editor.
Minor doc update.