VPN Support committed

[Dan Williams <dcbw redhat com>]

So what I've been working on the past week is VPN support.  I will now
apply the accumulated patches :)

VPN support is limited to 'vpnc' at this time, but I plan to eventually
do openswan if nobody else gets there first.

General Architecture:

- The panel applet has a new menu item called "VPN Connections", which
has a submenu that lists your VPN connections by name, and a "Disconnect
VPN" item to stop the active VPN.

- VPN connection information is stored in the Info daemon, and with the
current GNOME NMI implementation, that means GConf.  Its simply dbus
calls from NM to the Info daemon, which means its portable, of course,
to KDE or anything else.

- All different VPN services (ie vpnc, openswan, cisco, etc) drop a
".name" file into /etc/NetworkManager/VPN/ which contains their D-BUS
service name and a path to the VPN service's daemon.  When a VPN
connection that uses that VPN service is activated, NetworkManager will
run the VPN service daemon specified, and talk only to that VPN service
daemons D-BUS service.

- VPN implementation is up to the VPN service.  The 'vpnc' VPN service
daemon launches vpnc upon request, and makes vpnc call a helper daemon
that returns the IP configuration to the service.  It then signals the
bus of the new configuration, which NetworkManager picks up.

I'll write up a document at some point that describes this in more
detail.

Dan