RM: knights/testing -- RM; RC-buggy, Does not build, not ported to KDE4

[Jari Aalto <jari.aalto@cante.net>]

Consider removing knights:

    SERIOUS
    knights: build depends kdebase-kio-plugins no longer exists (need porting to KDE4)
    http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=528348

    IMPORTANT
    knights: obsolete build-dep on x-dev
    http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=515376

The application does not build. Needs porting to KDE4 which hasn't been
done since the bug #528348 was reported 2009-05-14.