libnm/libnm-util: add VPN 'persistent' property
vpn: allow plugins to re-enter the STARTING state to indicate reconnect

If the VPN re-enters the STARTING state to indicate that it has
disconnected from the VPN server and is trying to reconnect, change
the VPN connection's state to indicate that connectivity may be
limited.  Wait for the VPN to provide updated IP configuration
information from the reconnect to change back to the ACTIVATED
state.
vpn: add plugin 'can-persist' key

If set to 'yes', and the VPN connection specifies persistence, then
NetworkManager will allow the VPN connection to stay up over link
changes.
vpn/core: move VPN gateway route between devices when routing changes
vpn: reconnect on service failures (bgo #349151)

Attempt to reconnect the VPN on failures, except when the underlying
device fails.

https://bugzilla.gnome.org/show_bug.cgi?id=349151
clients: move secret agent to common directory

The agent code will be shared by both nmtui and nmcli.
clients: add real property name to NmSecretAgentSimpleSecret

It is necessary to identify secrets uniquely in nmcli.
cli: use secret agent for getting passwords from user

--ask option has to be used, so that nmcli can be interactive.
cli: add 'passwd-file' option for 'nmcli connection up' to provide passwords

It is useful for running nmcli without --ask option, i.e non-interactively.

Example contents of the file:
wifi.psk: s e c r e t 12345
802-1x.password:kili manjaro
802-1x.pin:987654321
clients: add common code for polkit agent listener

that can be used by nmcli and nmtui
configure: check whether polkit-agent-1 is available
cli: add a polkit agent support for nmcli

Example: nmcli --ask general hostname computer007
fixup! vpn/core: move VPN gateway route between devices when routing changes

Also add gs_unref attribute, so that codepaths that fail g_return() are
not completely broken by leaking a reference
fixup! vpn/core: move VPN gateway route between devices when routing changes
dhcp: add systemd DHCP code

This is a direct dump from systemd git on 2014-10-28, git commit
c4ac990007.  Only relevant files were included.

    SYSTEMD_DIR=../systemd
    COMMIT=c4ac990007cd0069bb7e76ec15dd731320f382fd

    mkdir -p ./src/dhcp-manager/systemd-dhcp/src/libsystemd-network/
    mkdir -p ./src/dhcp-manager/systemd-dhcp/src/shared/
    mkdir -p ./src/dhcp-manager/systemd-dhcp/src/systemd/

    (
       cd "$SYSTEMD_DIR"
       git checkout "$COMMIT"
       git clean -fdx
    )
    /bin/cp "$SYSTEMD_DIR"/src/libsystemd-network/dhcp-internal.h ./src/dhcp-manager/systemd-dhcp/src/libsystemd-network/dhcp-internal.h
    /bin/cp "$SYSTEMD_DIR"/src/libsystemd-network/dhcp-lease-internal.h ./src/dhcp-manager/systemd-dhcp/src/libsystemd-network/dhcp-lease-internal.h
    /bin/cp "$SYSTEMD_DIR"/src/libsystemd-network/dhcp-network.c ./src/dhcp-manager/systemd-dhcp/src/libsystemd-network/dhcp-network.c
    /bin/cp "$SYSTEMD_DIR"/src/libsystemd-network/dhcp-option.c ./src/dhcp-manager/systemd-dhcp/src/libsystemd-network/dhcp-option.c
    /bin/cp "$SYSTEMD_DIR"/src/libsystemd-network/dhcp-packet.c ./src/dhcp-manager/systemd-dhcp/src/libsystemd-network/dhcp-packet.c
    /bin/cp "$SYSTEMD_DIR"/src/libsystemd-network/dhcp-protocol.h ./src/dhcp-manager/systemd-dhcp/src/libsystemd-network/dhcp-protocol.h
    /bin/cp "$SYSTEMD_DIR"/src/libsystemd-network/dhcp6-internal.h ./src/dhcp-manager/systemd-dhcp/src/libsystemd-network/dhcp6-internal.h
    /bin/cp "$SYSTEMD_DIR"/src/libsystemd-network/dhcp6-lease-internal.h ./src/dhcp-manager/systemd-dhcp/src/libsystemd-network/dhcp6-lease-internal.h
    /bin/cp "$SYSTEMD_DIR"/src/libsystemd-network/dhcp6-network.c ./src/dhcp-manager/systemd-dhcp/src/libsystemd-network/dhcp6-network.c
    /bin/cp "$SYSTEMD_DIR"/src/libsystemd-network/dhcp6-option.c ./src/dhcp-manager/systemd-dhcp/src/libsystemd-network/dhcp6-option.c
    /bin/cp "$SYSTEMD_DIR"/src/libsystemd-network/dhcp6-protocol.h ./src/dhcp-manager/systemd-dhcp/src/libsystemd-network/dhcp6-protocol.h
    /bin/cp "$SYSTEMD_DIR"/src/libsystemd-network/network-internal.c ./src/dhcp-manager/systemd-dhcp/src/libsystemd-network/network-internal.c
    /bin/cp "$SYSTEMD_DIR"/src/libsystemd-network/network-internal.h ./src/dhcp-manager/systemd-dhcp/src/libsystemd-network/network-internal.h
    /bin/cp "$SYSTEMD_DIR"/src/libsystemd-network/sd-dhcp-client.c ./src/dhcp-manager/systemd-dhcp/src/libsystemd-network/sd-dhcp-client.c
    /bin/cp "$SYSTEMD_DIR"/src/libsystemd-network/sd-dhcp-lease.c ./src/dhcp-manager/systemd-dhcp/src/libsystemd-network/sd-dhcp-lease.c
    /bin/cp "$SYSTEMD_DIR"/src/libsystemd-network/sd-dhcp6-client.c ./src/dhcp-manager/systemd-dhcp/src/libsystemd-network/sd-dhcp6-client.c
    /bin/cp "$SYSTEMD_DIR"/src/libsystemd-network/sd-dhcp6-lease.c ./src/dhcp-manager/systemd-dhcp/src/libsystemd-network/sd-dhcp6-lease.c
    /bin/cp "$SYSTEMD_DIR"/src/shared/async.h ./src/dhcp-manager/systemd-dhcp/src/shared/async.h
    /bin/cp "$SYSTEMD_DIR"/src/shared/fileio.c ./src/dhcp-manager/systemd-dhcp/src/shared/fileio.c
    /bin/cp "$SYSTEMD_DIR"/src/shared/fileio.h ./src/dhcp-manager/systemd-dhcp/src/shared/fileio.h
    /bin/cp "$SYSTEMD_DIR"/src/shared/list.h ./src/dhcp-manager/systemd-dhcp/src/shared/list.h
    /bin/cp "$SYSTEMD_DIR"/src/shared/macro.h ./src/dhcp-manager/systemd-dhcp/src/shared/macro.h
    /bin/cp "$SYSTEMD_DIR"/src/shared/refcnt.h ./src/dhcp-manager/systemd-dhcp/src/shared/refcnt.h
    /bin/cp "$SYSTEMD_DIR"/src/shared/siphash24.c ./src/dhcp-manager/systemd-dhcp/src/shared/siphash24.c
    /bin/cp "$SYSTEMD_DIR"/src/shared/siphash24.h ./src/dhcp-manager/systemd-dhcp/src/shared/siphash24.h
    /bin/cp "$SYSTEMD_DIR"/src/shared/socket-util.h ./src/dhcp-manager/systemd-dhcp/src/shared/socket-util.h
    /bin/cp "$SYSTEMD_DIR"/src/shared/sparse-endian.h ./src/dhcp-manager/systemd-dhcp/src/shared/sparse-endian.h
    /bin/cp "$SYSTEMD_DIR"/src/shared/strv.c ./src/dhcp-manager/systemd-dhcp/src/shared/strv.c
    /bin/cp "$SYSTEMD_DIR"/src/shared/strv.h ./src/dhcp-manager/systemd-dhcp/src/shared/strv.h
    /bin/cp "$SYSTEMD_DIR"/src/shared/time-util.c ./src/dhcp-manager/systemd-dhcp/src/shared/time-util.c
    /bin/cp "$SYSTEMD_DIR"/src/shared/time-util.h ./src/dhcp-manager/systemd-dhcp/src/shared/time-util.h
    /bin/cp "$SYSTEMD_DIR"/src/shared/utf8.c ./src/dhcp-manager/systemd-dhcp/src/shared/utf8.c
    /bin/cp "$SYSTEMD_DIR"/src/shared/utf8.h ./src/dhcp-manager/systemd-dhcp/src/shared/utf8.h
    /bin/cp "$SYSTEMD_DIR"/src/shared/util.c ./src/dhcp-manager/systemd-dhcp/src/shared/util.c
    /bin/cp "$SYSTEMD_DIR"/src/shared/util.h ./src/dhcp-manager/systemd-dhcp/src/shared/util.h
    /bin/cp "$SYSTEMD_DIR"/src/shared/in-addr-util.c ./src/dhcp-manager/systemd-dhcp/src/shared/in-addr-util.c
    /bin/cp "$SYSTEMD_DIR"/src/shared/in-addr-util.h ./src/dhcp-manager/systemd-dhcp/src/shared/in-addr-util.h
    /bin/cp "$SYSTEMD_DIR"/src/systemd/_sd-common.h ./src/dhcp-manager/systemd-dhcp/src/systemd/_sd-common.h
    /bin/cp "$SYSTEMD_DIR"/src/systemd/sd-dhcp-client.h ./src/dhcp-manager/systemd-dhcp/src/systemd/sd-dhcp-client.h
    /bin/cp "$SYSTEMD_DIR"/src/systemd/sd-dhcp-lease.h ./src/dhcp-manager/systemd-dhcp/src/systemd/sd-dhcp-lease.h
    /bin/cp "$SYSTEMD_DIR"/src/systemd/sd-dhcp6-client.h ./src/dhcp-manager/systemd-dhcp/src/systemd/sd-dhcp6-client.h
    /bin/cp "$SYSTEMD_DIR"/src/systemd/sd-dhcp6-lease.h ./src/dhcp-manager/systemd-dhcp/src/systemd/sd-dhcp6-lease.h
    /bin/cp "$SYSTEMD_DIR"/src/systemd/sd-event.h ./src/dhcp-manager/systemd-dhcp/src/systemd/sd-event.h
    /bin/cp "$SYSTEMD_DIR"/src/systemd/sd-id128.h ./src/dhcp-manager/systemd-dhcp/src/systemd/sd-id128.h
sd-dhcp6-client: fix off-by-two error in DUID length

The duid data passed by the client does not include the DUID type,
but client->duid_len does account for the size of the DUID type.
sd-dhcp-client: support custom client IDs

Non-ethernet interface types use different client identifier formats,
plus when doing DHCPv4 and DHCPv6 on the same interface, the client
identifier should be related per RFC 4361.  Thus let the caller
override the existing MAC-based client identifier if necessary.
sd-dhcp-lease: load/save client ID

The lease is intimately tied to the client ID in use, so when loading
and renewing a lease, the same client ID should be used.
sd-dhcp-lease: expose load/save functions

They're useful outside of networkd itself.
sd-dhcp-client: clean up raw socket sd_event_source when creating UDP source

The raw socket sd_event_source used for DHCP server solicitations
was simply dropped on the floor when creating the new UDP socket
after a lease has been acquired.  Clean it up properly so we're
not still listening and responding to events on it.