Merge apt--mvo--0

Merge apt--mvo--0
Patches applied:

 * michael.vogt@ubuntu.com--2005/apt--mvo--0--patch-2
   * merge with matts tree, added documentation for the gpgv stuff

 * michael.vogt@ubuntu.com--2005/apt--mvo--0--patch-3
   * added gpgv::Options to configure-index

 * michael.vogt@ubuntu.com--2005/apt--mvo--0--patch-4
   * PulseIntervall can be configured now to make frontends like synaptic hayppy. it's done in a way that does not break binary compatibility

 * michael.vogt@ubuntu.com--2005/apt--mvo--0--patch-5
   * fix for apt-get update removing the cdroms Release.gpg files

 * michael.vogt@ubuntu.com--2005/apt--mvo--0--patch-6
   * path scoring changed, the non-symlink path is scored highest