[Sugar-devel] [DESIGN] Rework the wireless control panel section to respect non-wireless connections

[Frederick Grose]

Fixes #4410  https://bugs.sugarlabs.org/ticket/4410

The 'Discard network history' button is peculiar to Sugar, and
is destructive to all non-wireless connections, despite being in
the 'Wireless' section of the control panel.

In the proposed patch[0], the code variables and functions are
renamed and coded to be specific to wireless connections.

The 'Radio' checkbox instruction and 'Discard ...' button are
reworded to avoid confusion over their state and actions.[1]

If wireless hardware is not present on the system, the 'Wireless'
section of the control panel is excluded.[2]

[0,1,2] - https://github.com/sugarlabs/sugar/pull/228