Add scroll height indicators to Flickable

Fact* espVersion = getFact(FactSystem::ParameterProvider, MAV_COMP_ID_UDP_BRIDGE, "SW_VER"); crashes unit test if the parameter does not exist (which is exactly what the call is trying to establish).

At that point the vehicle is gone, so need to to clean it up

Takes less real estate and flows better and small displays

There are many ways of iterating over lists in C++/Qt.
In the specific case of QStrings, it is known [1] that using
foreach with const references avoids the creation of new
QString objects in each iteration, reducing the time consumed
by the loops.

[1] https://blog.qt.io/blog/2009/01/23/iterating-efficiently/Signed-off-by: Anselmo L. S. Melo <anselmo.melo@intel.com>

Refactored PX4 radio config to work with both PX4 and APM

Windows OS doesn’t disconnect port when you pull plug on USB. This
caused all sorts of problems with previous logic. New logic handles
this correctly.