- rename files mate-document-viewer -> atril
- up to 1.8.0
- rename mate-document-viewer -> atril
- adjust for renamed mate-file-manager -> caja
- build against libsecret (mate-keyring is now obsolete in favour of
  gnome-keyring)
- mate-doc-utils replaced by yelp-tools
- add libtiff-devel version dep based on error message