bgp: keep and use nexthop value as a string internally

Instead of BGPPathAttributeNextHop, keep nexthop value as a string.
Convert it to string as we get Update msg.

Signed-off-by: ISHIDA Wataru <ishida.wataru@lab.ntt.co.jp>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
packet/bgp: add route distinguisher classes and refine codes

Signed-off-by: ISHIDA Wataru <ishida.wataru@lab.ntt.co.jp>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
bgp: fix bug of exchanging paths between vrf and global_table

Signed-off-by: ISHIDA Wataru <ishida.wataru@lab.ntt.co.jp>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
bgp: fix typo

Signed-off-by: ISHIDA Wataru <ishida.wataru@lab.ntt.co.jp>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
bgp: remove unnecessary OutgoingRoute attribute 'bgp4_format'

Attribute 'bgp4_format' was intended to be used to decide whether to
construct UPDATE msg in bgp4 format or mpbgp format.
But we can decide this simply by checking the path type which we are going
update. If the path type is IPv4, we use bgp4 format. In other cases,
we use mpbgp format.

Signed-off-by: ISHIDA Wataru <ishida.wataru@lab.ntt.co.jp>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
ofctl_v1_2: fix pep8

ryu/lib/ofctl_v1_2.py:444:15: E127 continuation line over-indented for visual indent

Signed-off-by: TAKAHASHI Minoru <takahashi.minoru7@gmail.com>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
ofctl_v1_2: fix errors of get_flow_stats

following match fields caused an exception at get_flow_stats command:

  ipv6_nd_sll, ipv6_nd_tll

this patch fixes this problem.

Signed-off-by: TAKAHASHI Minoru <takahashi.minoru7@gmail.com>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
doc: add test-vrrp page

port from wiki page.

Signed-off-by: Yoshihiro Kaneko <ykaneko0929@gmail.com>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
doc: add test-of-config-with-linc page

port from wiki page.

Signed-off-by: Yoshihiro Kaneko <ykaneko0929@gmail.com>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>