add the irc channel to the readme file
add the irc channel to the readme file

Change-Id: Iaa3286c00f6a77202817e17bececed0c05af660f
Signed-off-by: Doug Hellmann <0798ebecfb7bc4dfb9d0445c2fa030eb64e1fa1c@doughellmann.com>

openstack/reno