add basic summary for tag nodes
add basic summary for tag nodes

svn path=/trunk/KDE/kdepim/akregator/; revision=426909

lefou/kdepim-noakonadi,lefou/kdepim-noakonadi,lefou/kdepim-noakonadi,lefou/kdepim-noakonadi,lefou/kdepim-noakonadi,lefou/kdepim-noakonadi