Meta tags for description, author, and keywords are generated,
except if meta robots "noindex" is forced (with some pages like search, recent cats, etc.).
In addition, $conf['meta_ref'] = false is forcing "noindex, nofollow".
merge -c3040 from branch 2.0 to trunk
git-svn-id: http://piwigo.org/svn/trunk@3041 68402e56-0260-453c-a942-63ccdbb3a9ee