maint: Cleanup C++ code to follow Octave coding conventions. Try to wrap long lines to < 80 characters. Use GNU style and don't indent first brace of function definition. "case" statement is aligned flush left with brace of switch stmt. Remove trailing '\' line continuation from the end of #define macros. Use 2 spaces for indent. * files-dock-widget.cc, history-dock-widget.cc, main-window.cc, octave-cmd.cc, octave-dock-widget.cc, octave-gui.cc, resource-manager.cc, settings-dialog.cc, shortcut-manager.cc, welcome-wizard.cc, workspace-view.cc, cellfun.cc, data.cc, debug.cc, debug.h, dirfns.cc, error.h, file-io.cc, gl-render.cc, gl-render.h, gl2ps-renderer.h, graphics.cc, graphics.in.h, help.cc, input.cc, load-path.cc, load-path.h, lookup.cc, lu.cc, oct-stream.cc, octave-default-image.h, ordschur.cc, pr-output.cc, qz.cc, strfns.cc, symtab.cc, symtab.h, sysdep.cc, variables.cc, zfstream.h, __fltk_uigetfile__.cc, __init_fltk__.cc, __magick_read__.cc, __osmesa_print__.cc, audiodevinfo.cc, ov-classdef.cc, ov-classdef.h, ov-fcn.h, ov-float.cc, ov-flt-complex.cc, ov-java.cc, ov-range.cc, ov-re-mat.cc, ov-usr-fcn.h, ov.cc, op-int.h, options-usage.h, pt-eval.cc, Array-C.cc, Array-fC.cc, Array.cc, Array.h, PermMatrix.cc, Sparse.cc, chMatrix.h, dSparse.cc, dim-vector.h, bsxfun-decl.h, bsxfun-defs.cc, oct-norm.cc, Sparse-op-defs.h, oct-inttypes.cc, oct-inttypes.h, main.in.cc, mkoctfile.in.cc: Cleanup C++ code to follow Octave coding conventions.

--- a/libinterp/corefcn/sysdep.cc
+++ b/libinterp/corefcn/sysdep.cc
@@ -186,7 +186,7 @@
 #endif
 
 DEFUN (__open_with_system_app__, args, ,
-           "-*- texinfo -*-\n\
+       "-*- texinfo -*-\n\
 @deftypefn {Loadable Function} {} __open_with_system_app__ (@var{file})\n\
 Undocumented internal function.\n\
 @end deftypefn")
@@ -1017,7 +1017,7 @@
 // needed for X11 and Carbon functions.
 
 DEFUN (have_window_system, , ,
-  "-*- texinfo -*-\n\
+       "-*- texinfo -*-\n\
 @deftypefn {Built-in Function} {} have_window_system ()\n\
 Return true if a window system is available (X11, Windows, or Apple OS X)\n\
 and false otherwise.\n\