- changes comment number and value from nodes to attibutes
- UPdate bom_with_title_block_2_csv to use the changes made for sheet and comment

- update bom_with_title_block_2_csv.xsl

- the net file now has all project sheet title block using node 'sheets' and 'sheet'
- Updated bom_with_title_block_2_csv. Note, its only going to output the root title block.

- corrected the code that violated the code policy. i.e. added the extra space to make the code more readable
- Restored bom2csv.xsl to its original form 
- Added bom_with_title_block_2_csv.xsl which has the new BOM generator.

-update XNODE* NETLIST_EXPORT_TOOL::makeGenericDesignHeader() so that the net file now outputs project information.
    For example:
        - Company name
        - Project title
        - issue date
        - Revision
        - Comment 1 to 4

- updated bom2csv.xsl plugin to take advatage of the extra project information that the net file now outputs.

Overall this improvement will make it easier to automatically make controlled and traceable documents.

Prevent Pcbnew edit graphics property dialog from excepting zero length objects.  (fixes lp:1392117)

Pcbnew: fix Bug #1418135 (scrollbars never shown in design rules dialog, in netclasses grid list, which prevent to use many netclasses). Also fix very minor other issues.

* Using a Web navigator embedded in Kicad can create security issues in Kicad.
* The web kit is not always easily available on Linux.
* There is now a tool in kicad fp lib wizard  to list and select the .pretty libs available on Github Kicad repo (When the kicad plugin is selected, this tool can download and make a local copy of these libs)
However, using -D KICAD_USE_WEBKIT=ON when invoking  cmake still build the embedded web viewer.

Pcbnew - plot dialog: fix Bug #1417435 (Gerber(and some others)  plot mode is fixed as”sketch” instead of "filled" )

Dialogs edit footprint in module editor and edit footprint in board editor: add button to edit the selected 3D shape filename.
Dialog edit component in library editor: add button to edit the selected footprint filter.

Dialogs edit footprint in module editor and edit footprint in board editor: add button to edit the selected 3D shape filename.
Dialog edit component in library editor: add button to edit the selected footprint filter.

Pcbnew: simplify draw code in  default canvas and plot functions by removing the plot LINE option, which is not existing in all plotters, not existing in opengl/cairo canvas, and not usefull in default canvas.

ModEdit: add a settings menu option(and the corresponding dialog) to set default values used when creating a footprint or add graphic items to a footprint being edited.
These settings are now not common to the board editor, because the footprint editor can be run outside the board editor.
download_boost.cmake: ignore  .htm* files when installing boost. They are not used, and often have a very very long (and stupid) name which sometimes creates issues.

Class BOARD: Rename an overloaded method named SetLayer with the better name SetLayerDescr, and comment it. It also remove some warnings when compiled with option -Woverloaded-virtual

* Fix -Woverloaded-virtual warning in DIALOG_LIB_NEW_COMPONENT class
  definition.
* Make EDA_ITEM::Matches( const wxString& wxFindReplaceData& ) protected
  since it's a helper function that should only be called by derived objects.

Footprint Editor: New footprint creation: change defaults for ref and value texts: now Ref text is REF** and Value text  is the footprint name. Also Value is put on fab layer (front)
muonde.cpp: cleanup this very old code, and fix not working code.

* Check to see if image handler is already initialized to prevent warning
  on debug builds.
* Change LIB_PART destructor message output to use wxLogDebug for debugging
  on windows builds.
* Minor code cleaning and coding policy fixes.

Fix minor aesthetic issues in dialogs (these minor issues (overlapping widgets)  exit only with some Windows managers like KDE)

Pcbnew: fix Bug #1413701 (Segfault on highlight "unconnected" net 0 in Pcbnew ). Also, remove now useless code and other very minor fixes.

Pcbnew: fix issues and potential issues when reading board files and mainly old board files, and enhance the DRC tests and Delete Single Pad Net option when reading a netlist:
* Delete Single Pad Net option does not delete the net if a zone use this net (i.e. is attached to this pad).
* pcb_parser accept now negative netcodes in zones (can happen with old files, which previously could crash Pcbnew)
* pcb_parser accept now files with incorrect or missing net count  (can happen with old files, which previously could crash Pcbnew)
* if a zone has a non-existent net name it now keep this net name, and DRC detect it (previously, the net name was lost, and the DRC did not tected this issue).
* Drc test: now detect a "dead" net, i.e. a net with 0 pads, but still used by a zone. It happens easily after a schematic modification, when a net disappears or is renamed.

Eeschema: fix a minor bug and enhances SCH_MARHER::Matches function (  partial use of  0005-SCH_MARKER-fix-a-Woverloaded-virtual.patch, from <fatzer2@gmail.com> ) and other very minor fix.

Pcbnew, layers manager: Fix an annoying bug I added in rev 5359, in Render options: in Board editor many render options were not displayed (similar fp editor mode).
Now fixed.