meta-google: gbmc-ip-monitor: Add package

Add a daemon that monitors all link / addr / route changes on a system,
and runs a set of installed hooks to perform customized behavior when
these changes occur.

Change-Id: Id2a6b7dc2534ebae1beca7135528a6e1e4eada57
Signed-off-by: William A. Kennington III <wak@google.com>
diff --git a/meta-google/recipes-google/networking/files/gbmc-ip-monitor.service b/meta-google/recipes-google/networking/files/gbmc-ip-monitor.service
new file mode 100644
index 0000000..435eac9
--- /dev/null
+++ b/meta-google/recipes-google/networking/files/gbmc-ip-monitor.service
@@ -0,0 +1,9 @@
+[Unit]
+Before=systemd-networkd.service
+
+[Service]
+Type=notify
+ExecStart=/usr/libexec/gbmc-ip-monitor.sh
+
+[Install]
+WantedBy=multi-user.target