configurehood: Introduce random delays to dilute requests

Instead of having 1000 routers accessing the KeyXchange in the
same second, this will dilute the request within a period of
15 seconds.

Same is done for queries from gateways.

Signed-off-by: Adrian Schmutzler <freifunk@adrianschmutzler.de>
Reviewed-by: Robert Langhammer <rlanghammer@web.de>
Reviewed-by: Christian Dresel <fff@chrisi01.de>

src/packages/fff/fff-hoods/files/usr/lib/micron.d/fff-hoods

-3-59/5 * * * * [ -f /tmp/started ] && /usr/sbin/configurehood
+3-59/5 * * * * /bin/sleep $(/usr/bin/random 1 15); [ -f /tmp/started ] && /usr/sbin/configurehood