Fix grammar issues with release notes. Make the wording clearer for
a few of them as well.
Change-Id: If766f222c57f490276de717618ebb7102e7efdcb
Signed-off-by: Kyle Mestery <mestery@mestery.com>
L3-agent router_id option has been defined in order to associate a
l3-agent to a specific router when use_namespaces=False. The option
use_namespaces has been removed in Mitaka, so router_id option is no
longer needed and can be deprecated in order to prepare its removal in N
cycle.
Closes-Bug: #1518776
Change-Id: Id79499ccbf3ea69ca4cd7e4b2f812f6dbc0406e0