doc: Release Notes for GlusterFS 3.6.0

Signed-off-by: Niels de Vos  <ndevos@redhat.com>
Signed-off-by: Venky Shankar <vshankar@redhat.com>
Signed-off-by: Vijay Bellur  <vbellur@redhat.com>
Signed-off by: Emmanuel Dreyfus <manu@netbsd.org>
Signed-off by: Kaushal Madappa <kmadapp@redhat.com>
Signed-off by: Krishnan Parthasarathi <kparthas@redhat.com>
Signed-off by: Xavier Hernandez <xhernandez@datalab.es>
Signed-off by: Harshavardhana <harsha@harshavardhana.net>
Signed-off-by: Ravishankar N <ravishankar@redhat.com>

Change-Id: I9973f70eedabf408c452d4018d7521e8b59fb4a7
Reviewed-on: http://review.gluster.org/8993
Reviewed-by: Vijay Bellur <vbellur@redhat.com>
Tested-by: Vijay Bellur <vbellur@redhat.com>