On nRF devices if we print with the NUS console disconnected (instead
of never connected) then things we can end up hanging. Better only
to print an exception if the watch class contains a method to do
that.
This is getting us much closer to the final UI concept. We have a
quick ring from which we can select typical apps such as clock and
stopwatch which will (eventually) be supplemented with step counting
and heart rate monitoriing. More exotic apps (currenrtly torch, self
test, settings) are all relagated to the launcher ring.
If an application crashes let's report it on the device so it can be
distinguished from a hang (if nothing else it should mean we get better
bug reports).
This might be a reasonable preference for the setings but, more importantly,
we can also set blank_after to very high values to ensure the watch doesn't
sleep during the voice over in videos!
Here the biggest changes are in the test application because we
refactor a number of the tests to make better use of the button.
Although applications may consume button events it does have a
default behavior which is to switch to the default application
(usually the clock).
This is a big change that break compatiblity with existing applications
*and* with existing installed versions of main.py.
When upgrading it is import to update main.py:
./tools/wasptool --upload wasp/main.py
