Permit ICMPv6 RAs only from known routers

Currently ingress ICMPv6 RAs are permitted from any IPs by
default to allow VMs to accept ICMPv6 RA from provider network.
In this way, VM can accept RAs from attacker VM and configure
a network prefix specified by the attacher VM.

Remove permitting ICMPv6 RAs from any IPs and add security rule
to only permit ICMPv6 RA from:

1. If the port's subnet is configured with ipv6_ra_mode value
(i.e.value is slaac, dhcpv6-stateful, or dhcpv6-stateless), RA
is sending from dnsmasq controlled by OpenStack. In this case,
allow RA from the link local address of gateway port (if the
gateway port is created).

2. If the subnet's gateway port is not managed by OpenStack, allow
the ICMPv6 RA sent from the subnet gateway IP if it's a link local
address. The administrator needs to configure the gateway IP as
link local address in this case to make the RA rule work.

Change-Id: I1d5c7aaa8e4cf057204eb746c0faab2c70409a94
Closes-Bug: 1262759
Replace HTTPSConnection in NEC plugin

Replace HTTPSConnection in NEC plugin PFC driver with Requests.

SSL Verification is from now on enabled by default.

This changes the default behaviour and is the primary intention of this
change: verify SSL certificates.

This might break existing configuration/setups where the SSL certificate
used by the NEC PFC driver would not pass the verification.

SecurityImpact
DocImpact
Partial-Bug: 1188189

Change-Id: I1e5fdc9c2ed5b812aa6509d1639bd499acc5c337
Fix Jenkins translation jobs

The job neutron-propose-translation-update
does not update from
transifex since our po files contain duplicate entries where
obsolete entries duplicate normal entries.

Remove all obsolete entries to fix the job.

Add test to pep8 that checks that no new breakages get
introduced.

Change-Id: I9c680eeefecfa124c5b2900b7fa7a0a8f7e8ebd6
Closes-Bug: #1299349
Add a note that rpc_workers option is experimental

blueprint multiple-rpc-workers

Change-Id: Id354b96fc591752e1e79b072997423b6447d5de9
Merge "Replace HTTPSConnection in NEC plugin"
Merge "Fix Jenkins translation jobs"
Merge "Add a note that rpc_workers option is experimental"
Merge "Permit ICMPv6 RAs only from known routers"