make copying figures to clipboard work (bug #44866) * Figure.cc (Figure::copy_figure_callback): Just print the figure to a file here, then call octave_link::copy_image_to_clipboard. (delete_file): Delete unused static function. * main-window.h, main-window.cc (main_window::copy_image_to_clipboard): New function. (main_window::construct_octave_qt_link): Connect octave_qt_link::copy_image_to_clipboard_signal signal to main_window::copy_image_to_clipboard slot. * octave-qt-link.h, octave-qt-link.cc (octave_qt_link::do_copy_image_to_clipboard): New function. (octave_qt_link::copy_image_to_clipboard_signal): New signal. * octave-link.h (octave_link::do_copy_image_to_clipboard): New pure virtual function. (octave_link::copy_image_to_clipboard): New static funtion.

GNULIB_LINK_DEPS = \
  $(COPYSIGNF_LIBM)\
  $(COPYSIGN_LIBM)\
  $(FLOORF_LIBM)\
  $(FLOOR_LIBM)\
  $(GETHOSTNAME_LIB)\
  $(LIBSOCKET)\
  $(LIB_NANOSLEEP)\
  $(LIB_SELECT)\
  $(LTLIBINTL)\
  $(ROUNDF_LIBM)\
  $(ROUND_LIBM)\
  $(TRUNCF_LIBM)\
  $(TRUNC_LIBM)

LIBOCTAVE_LINK_DEPS = \
  $(GNULIB_LINK_DEPS) \
  $(CURL_LIBS) \
  $(SPARSE_XLIBS) \
  $(ARPACK_LIBS) \
  $(QRUPDATE_LIBS) \
  $(FFTW_XLIBS) \
  $(LAPACK_LIBS) \
  $(BLAS_LIBS) \
  $(READLINE_LIBS) \
  $(TERM_LIBS) \
  $(LIBGLOB) \
  $(PCRE_LIBS) \
  $(DL_LIBS) \
  $(PTHREAD_LIBS) \
  $(FLIBS) \
  $(LIBS)

LIBOCTAVE_LINK_OPTS = \
  $(CURL_LDFLAGS) \
  $(SPARSE_XLDFLAGS) \
  $(ARPACK_LDFLAGS) \
  $(QRUPDATE_LDFLAGS) \
  $(FFTW_XLDFLAGS)