slowly working towards a value-based interface to KMFilter: removed virtuals
slowly working towards a value-based interface to KMFilter: removed virtuals

svn path=/trunk/kdenetwork/kmail/; revision=168321

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