Merge branch '-renato' into stable/2.0

This contains bgp memory leak fixes as well as cleanups to VRF/namespace
handling and has been run through extended testing in Cumulus' testbed:

Tested-by: Donald Sharp <sharpd@cumulusnetworks.com>

diff --cc bgpd/bgp_route.c
Simple merge

diff --cc bgpd/bgpd.c
Simple merge

diff --cc lib/command.c
Simple merge

diff --cc lib/if.c
Simple merge

diff --cc zebra/interface.c
Simple merge

diff --cc zebra/zebra_mpls.c
Simple merge

diff --cc zebra/zebra_rib.c
Simple merge

diff --cc zebra/zebra_rnh.c
Simple merge