This 'Packages' shortcut helper can be used for simplified
usage of grep-aptavailable from dctrl-tools.

Rather than needing to specify the following explicit command:

  ! grep-aptavail -n -sPackage -FPriority standard

in package lists, the following shortcut can be used:

  ! Packages Priority standard

Updating internal variables from lh to lb scheme, should be the last piece to finish the live-helper to live-build rename.

By using APT_OPTIONS and APTITUDE_OPTIONS in config/common,
one can manipulate the default options wich is made to each
and every apt and aptitude call.