device: fix fetching the IPv6 default route for assumed devices

Signed-off-by: Thomas Haller <thaller@redhat.com>
core: don't pass NULL for "%s" format to g_message

Signed-off-by: Thomas Haller <thaller@redhat.com>
core: fix integer type of mtu variable

Signed-off-by: Thomas Haller <thaller@redhat.com>
man: add manual page for nmtui(1)

https://bugzilla.gnome.org/show_bug.cgi?id=739710

Branch: th/bgo739710_man_nmtui
Signed-off-by: Thomas Haller <thaller@redhat.com>
keyfile: don't assert when parsing invalid prefix

Signed-off-by: Thomas Haller <thaller@redhat.com>
cli: show gateway as a separate item in active connection data (bgo #739958)

Example (for active connection ethernet-13)
$ nmcli -f active con show ethernet-13
...
IP4.ADDRESS[1]:                         10.34.25.205/23
IP4.GATEWAY:                            10.34.25.254
IP4.ROUTE[1]:                           dst = 10.38.5.26/32, nh = 0.0.0.0, mt = 20
...

https://bugzilla.gnome.org/show_bug.cgi?id=739958
dhcp: fix adapter for sd logging macros to show file location

Previously we were logging:
   <debug> [1415715440.639086] [__FILE__:__LINE__] client_set_lease_timeouts(): DHCP CLIENT (0xcf221f86): T1 expires in 11h 59min 53.566147s

Signed-off-by: Thomas Haller <thaller@redhat.com>
tui: fix generated new connection names

Now that "i" is being used in the first loop over all connections, we
need to reset it before using it again in the loop to find an
available name.
vpn: update DefaultRouteManager before sending state change signal

The DRM now affects DNS too, since it determines the "best" IPv4
and IPv6 configs based on it's idea of the default route.  The
Policy is also still updating DNS from a state-change handler for
VPN connections.

This led to a situation where the Policy would remove the VPN's
IP config from the DNS manager in vpn_connection_deactivated() and
call update_ip4_dns(), whereupon get_best_ip4_config()  returned
the just-removed VPN IPv4 config as "best" because the VPN connection
hadn't yet told the DefaultRouteManager to remove it.

Which meant VPN nameservers stuck around in resolv.conf for a long
time after the VPN was disconnected.

Fixes: a39a3ae4cd72d695f1b5d10eaa79544f2020a54e
core: remove unused variable