fix interface mapping slip-up in wxPoint EDA_DRAW_FRAME::GetCrossHairPosition( bool aInvertY ) const

Save grid origin in .kicad_pcb files only if not 0,0 (to keep compatibility with previous versions of pcbnew, mainly the stable version)
Very minor other fixes (set modify flag when grid origin is moved from the dialog grid)

split expression into two lines for verification while using debugger that GetScreen() is a virtualized call.

*) add hotkey for setting the grid origin as 'S', in board editor, module editor.
*) re-position the function interface for cursor movement from BASE_SCREEN into
   class EDA_DRAW_FRAME.  This is a prelude to getting rid of BASE_SCREEN or
   splitting it up.

Minor fixes. Minor code cleaning. Pcbnew: better iniatilization of members in DRAWSEGMENT, TRACK, EDGE_MOD (not bugs: just useful when using python scripting).

Minor code cleaning. Pcbnew: better iniatilization of members in DRAWSEGMENT, TRACK, EDGE_MOD (useful when using  python scripting).

convert to UTF-8, eeschema cannot load LATIN1 strings anymore.

All source files are supposed to be UTF-8 now.  Although not a source file, my editor
was tripping on this file when grepping.

Pl_Editor: title block texts can be multiline (use" \n" :  a '\' followed by a 'n' to create a new line inside a text)
Very minor code cleaning.

* Force search when wrap past end of list option changes state.
* Fix SCH_FIELD::Matches() for bug in user defined fields which have an ID
  of -1.
* Minor improvements to the find data names to improve source code readability.

Eeschema: fix a *very subtle* bug noticeable only in complex hierachies, for multiple parts per package:
sometimes, the modified flag was set for these components just when switching from a sheet to an other sheet.
Pcbnew: fix Bug #1197414 (dragged track segments does not show clearance area)

This keeps it out of the KiCad mode path, making that leaner and less confusing about
what is supported in KiCad mode.  Within KiCad mode, treat quoted vs. non-quoted tokens
as the two general categories, with non-quoted having sub-categories.  Eliminate  
an unimplemented, unused function declaration in DSNLEXER.
 
Improve the output formatting of THROW_PARSE_ERROR().