policy: Make the polkit policy not be desktop-centric

The polkit policy should allow admin users logged in via ssh
or Cockpit (for example on a server) to perform the actions
in question.  The <allow_any> applies non local sessions.

Signed-off-by: Richard Hughes <richard@hughsie.com>
hawkey: Port to libhif and rename the backend to "Hif"

It's disingenuous at best to call this the "hawkey" backend.
hif: Use hif_context_get_install_root()
packagekit: Add PK_ROLE_ENUM_GET_OLD_TRANSACTIONS to get-roles response
hif: Fix compile warning for new libhif versions
hif: Set the context parameters before setting it up
hif: Use the new hif_goal_get_packages() API from libhif
hif: Adapt to hif_package_set_action() API change
hif: Reimplement multiple kernel package installation

We had existing code that allowed us to keep multiple kernel packages
installed, but this had broken at some point. This commit reimplements it using
current hawkey API, simplifying code and making it work again.

Signed-off-by: Richard Hughes <richard@hughsie.com>
Update group list in the documenation