glib2-branding-openSUSE: Update gnome-defaults

This update fixes the following issue with glib2-branding-openSUSE:
- Update gnome_defaults: nautilus-folder-handlder has been dropped a while ago and the functionality merged into nautilus directly. This never really caused any issue, as nautilus was one of the few .desktop files registering a inode/directory MimeType. Since GNOME 3.10, baobab does that as well, resulting in situations where baobab can be prefered (the Mime handling is pseudo-random). (bnc#849914).
- Add %mime_database_post//%mime_database_postun macros to post and postun, to ensure installation triggers updating the mime database.

Fixed bugs
bnc#849914
Annoying: in some cases, 'directories' open in baobab instead of nautilus
Selected Binaries
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