doc: Release notes for 3.4.1

Change-Id: Id4bb25c3fbda52700b1d4d624cd622db3b3c0d8a
Signed-off-by: Vijay Bellur <vbellur@redhat.com>
BUG: 811311
Reviewed-on: http://review.gluster.org/6011
Reviewed-by: Krishnan Parthasarathi <kparthas@redhat.com>