partial cleanup of include files in gui sources * symbol-information.cc, octave-adapter/octave-event.cc: New files. * documentation-dockwidget.h, history-dockwidget.cc, m-editor/file-editor.h, octave-event.cc, octave-event.h, octave-link.cc, octave-link.h, octave-main-thread.cc, octave-gui.cc, symbol-information.cc, symbol-information.h, workspace-model.cc: Avoid including unnecssary header files.

((nil .
      ((c-file-style . "gnu")
       (indent-tabs-mode . nil)
       (fill-column . 72)
       (eval . (when (string-match "\\.h\\'" (buffer-file-name))
                 (unless (string-match "/gnulib/" (buffer-file-name))
                   (c++-mode)
                   (c-set-style "gnu"))))))
 (change-log-mode . ((indent-tabs-mode . t)))
 (makefile-mode . ((indent-tabs-mode . t))))