don't crash on "open homepage" action when the selected node is not a Feed
don't crash on "open homepage" action when the selected node is not a Feed

svn path=/trunk/KDE/kdepim/akregator/; revision=427016

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