Allow the memberlist shutdown even if networkdb leave fails
Allow the memberlist shutdown even if networkdb leave fails

Signed-off-by: Madhu Venugopal <d22477479bbf55ba62bd822f4112c80f292c7805@docker.com>

sainath14/libnetwork,msabansal/libnetwork,vdemeester/libnetwork,WeiZhang555/libnetwork,vdemeester/libnetwork,mahak/libnetwork,mbanikazemi/libnetwork,docker/libnetwork,mahak/libnetwork,abhi/libnetwork,mYmNeo/libnetwork,sainath14/libnetwork,vdemeester/libnetwork,medallia/libnetwork,msabansal/libnetwork,ityangchen/libnetwork,tmakita/libnetwork,ityangchen/libnetwork,kolyshkin/libnetwork,docker/libnetwork,cpuguy83/libnetwork,medallia/libnetwork,cpuguy83/libnetwork,abhi/libnetwork,mbanikazemi/libnetwork,fcrisciani/libnetwork,kolyshkin/libnetwork,docker/libnetwork,curtiszimmerman/libnetwork,tmakita/libnetwork,WeiZhang555/libnetwork,allencloud/libnetwork,medallia/libnetwork,mYmNeo/libnetwork,abhi/libnetwork,mahak/libnetwork,fcrisciani/libnetwork,kolyshkin/libnetwork,curtiszimmerman/libnetwork,allencloud/libnetwork