* merge lp:~mvo/apt/netrc branch, this adds support for a

* merge lp:~mvo/apt/netrc branch, this adds support for a
  /etc/apt/auth.conf that can be used to store username/passwords
  in a "netrc" style file (with the extension that it supports "/"
  in a machine definition). Based on the maemo git branch.
* apt-pkg/deb/dpkgpm.cc:
  - add "purge" to list of known actions