nm-applet doesn't indicate by default when networks are unencrypted

[Jeff Abrahamson]

It looks like nm knows about security, because `nmcli device wifi list` shows a column about security. But the graphical indicator doesn't warn me (nor is there a notification on connection) when the wifi network is unencrypted.

This is a security-related feature request: I think it should provide a warning, even if that warning is unactionnable beyond choosing possibly not to remain connected or to restrict some activities.

ProblemType: Bug
DistroRelease: Ubuntu 17.04
Package: network-manager-gnome 1.4.2-1ubuntu4
ProcVersionSignature: Ubuntu 4.10.0-33.37-generic 4.10.17
Uname: Linux 4.10.0-33-generic x86_64
NonfreeKernelModules: wl
ApportVersion: 2.20.4-0ubuntu4.5
Architecture: amd64
CurrentDesktop: i3
Date: Thu Sep 21 12:38:51 2017
EcryptfsInUse: Yes
IfupdownConfig:
 # interfaces(5) file used by ifup(8) and ifdown(8)
 auto lo
 iface lo inet loopback
InstallationDate: Installed on 2015-12-17 (644 days ago)
InstallationMedia: Ubuntu 15.04 "Vivid Vervet" - Release amd64 (20150422)
IpRoute:
 default via 10.176.32.1 dev wlp6s0 proto static metric 600
 10.176.32.0/20 dev wlp6s0 proto kernel scope link src 10.176.43.35 metric 600
 10.226.16.20 via 10.176.32.1 dev wlp6s0 proto dhcp metric 600
 169.254.0.0/16 dev docker0 scope link metric 1000 linkdown
 172.17.0.0/16 dev docker0 proto kernel scope link src 172.17.0.1 linkdown
NetworkManager.conf:
 [main]
 plugins=ifupdown,keyfile

 [ifupdown]
 managed=false
NetworkManager.state:
 [main]
 NetworkingEnabled=true
 WirelessEnabled=true
 WWANEnabled=false
SourcePackage: network-manager-applet
UpgradeStatus: Upgraded to zesty on 2017-06-06 (107 days ago)
nmcli-dev:
 DEVICE TYPE STATE DBUS-PATH CONNECTION CON-UUID CON-PATH
 docker0 bridge connected /org/freedesktop/NetworkManager/Devices/2 docker0 16dafb11-675e-4681-8ab2-77ab905406a6 /org/freedesktop/NetworkManager/ActiveConnection/0
 wlp6s0 wifi connected /org/freedesktop/NetworkManager/Devices/1 NYPL 3d406aa5-be38-4abe-a6c7-150fed39f880 /org/freedesktop/NetworkManager/ActiveConnection/10
 lo loopback unmanaged /org/freedesktop/NetworkManager/Devices/0 -- -- --
nmcli-nm:
 RUNNING VERSION STATE STARTUP CONNECTIVITY NETWORKING WIFI-HW WIFI WWAN-HW WWAN
 running 1.4.4 connected started full enabled enabled enabled enabled disabled