doesn't yet perisist across the whole app.  This is because we should:

(1) decide what goes in the navigation drawer vs. menus
(2) stop loading activities and start loading in fragments
(3) think about how to use fragments in a cool way.

will now use a drawer that will overlap the action bar, hiding the menu.
It's just a PoC, there is much more work to do.

… object get deleted )

created a progress dialog that will show up only if
a certain amount of time has been elapsed and disappear if
has been shown for at least another certain time.

show such progress dialog when changing interface
( stopping and starting network radar may require some second ).

another way is to asynchronous stopping the network-radar but
we should deregister receivers and we lost the STARTED/STOPPED
intents.

in a far future we will support more running instances of
network-radar, so you can be notified ( say, with a small icon over the interface name )
that new hosts appearead on interfaces that you are not watching.

it may require some data not available in the contructor.

…ess )