doc: Document libgfapi and its apis,usage,bindings..etc

Change-Id: I3435f9a88acafa905e879c68bb7aa8b16023cf02
BUG: 1086766
Signed-off-by: Humble Chirammal <hchiramm@redhat.com>
Signed-off-by: Soumya k <skoduri@redhat.com>
Reviewed-on: http://review.gluster.org/7865
Reviewed-by: Lalatendu Mohanty <lmohanty@redhat.com>
Reviewed-by: Niels de Vos <ndevos@redhat.com>
Tested-by: Niels de Vos <ndevos@redhat.com>
features/quota: unref and set priv->rpc_clnt to NULL once disabled.

Change-Id: Ic1a6bc36b26cf31f00644bd674b24daa11745e64
BUG: 1103636
Signed-off-by: Raghavendra G <rgowdapp@redhat.com>
Reviewed-on: http://review.gluster.org/7876
Reviewed-by: Krishnan Parthasarathi <kparthas@redhat.com>
Tested-by: Gluster Build System <jenkins@build.gluster.com>