Hints for gthumb in main

Warnings

• asv-circular-component-relation
  org.gnome.gThumb.appdata.xml:277 -
  This component extends, provides, requires or recommends itself, which is certainly not intended and may confuse users or machines dealing with this metadata.
• gettext-data-not-found
  Unable to find any translation data for specified Gettext domain 'gthumb'.
• no-translation-statistics
  We could not extract any translation statitics, althout metadata hints were given that the data exists. Please check the <translation/> MetaInfo tag for spelling mistakes. It also makes sense to ensure all locale files are placed in the right directories (e.g. gettext .mo files in /usr/share/locale/*/LC_MESSAGES/