Add gpdf-persist-file.cc.

Add gpdf-persist-file.cc.

* po/POTFILES.in: Add gpdf-persist-file.cc.

* xpdf/gpdf-persist-file.cc (gpdf_persist_file_class_init)
(impl_bonobo_persist_file_load): emit (new) loading-failed signal
if something goes wrong during load.

* xpdf/gpdf-persist-file.h: add slot for loading-failed.

* xpdf/gpdf-marshal.list: add VOID:STRING.

* xpdf/gpdf-links-canvas-layer.cc: fix include (thanks Remi).

* xpdf/gpdf-control.cc (gpdf_control_setup_persist)
(gpdf_control_destroy): on loading-failed signal, display error
alert.

* xpdf/eog-hig-dialog.h, xpdf/eog-hig-dialog.c: copied from eog;
HIG conforming alert dialog.

* xpdf/Makefile.am (libgpdf_a_SOURCES): build eog-hig-dialog

* NEWS: updated.