This adds the argument -f (--filenames-only), which only prints the
filenames of files containing German comments.
I personally scan the whole file for German strings anyway, as we do
not find German strings with less than 4 chars. So there's not so
much use in printing the found strings.

This option is useful for Intel AppUp builds. On the other hand,
unused STARTCENTER_LAYOUT_STYLE option was removed.

lp#527938, debian#602953, fdo#33266, i#105408: do not crash on clicking bibliography when base isnt installed

see commit 836d9864

ISCHECKFORPRODUCTUPDATES is a de-facto standard for enabling or
disabling Online Update feature. We had this property but it was
unused for a long time. Now LibreOffice can be installed with
msiexec /i LibO<version>.msi ISCHECKFORPRODUCTUPDATES=0 in order
to disable Online Update feature.

"PangoAttrIterator * pango_attr_list_get_iterator (PangoAttrList *list);

Returns : the newly allocated PangoAttrIterator, which should be freed with
pango_attr_iterator_destroy()."

and ClickLightHdl always takes a non-NULL argument, so NULL test is
pointless. Turn it into a normal method that takes a reference.
GetLightSource can be const. Nothing calls DoubleClickHdl, remove it.