Network: show Not Connected instead of Off when wifi radio is on

When wifi is powered but not connected, show Not Connected instead
of off. This avoids a Off status next to a Turn Off menu item.

https://bugzilla.gnome.org/show_bug.cgi?id=709043
NetworkMenu/NMConnectionDevice: fix status text

Be consistent with v4 mockups

https://bugzilla.gnome.org/show_bug.cgi?id=709043
NetworkMenu/NMDeviceModem: fix status texts for airplane mode

Show "Hardware Disabled" when disabled by HW switch, and
generically "Disabled" when airplane mode is active, as
indicated by v4 mockups.
Note that bluetooth is not affected by NM handling of airplane
mode (and generally the firmware makes the USB bluetooth
adapter disappear when rfkilled), so this is in NMDeviceModem
instead of NMConnectionDevice.

https://bugzilla.gnome.org/show_bug.cgi?id=709043
NetworkMenu/NMDeviceModem: use the operator name when we have it

Instead of the connection name, as the operator name is usually
shorter and more useful.

https://bugzilla.gnome.org/show_bug.cgi?id=709043
NetworkMenu: make the settings launcher point to the right devices

Tell gnome-control-center to focus on the associated device when
launching it from one of the submenus.

https://bugzilla.gnome.org/show_bug.cgi?id=709246