In the past, we always wrapped a HexAdapter around bytes-like data in
order to make sure it's printed as hex-digits. However, now that we are
doing JSON output it's much easier to let the pySim.utils.JsonEncoder
take care of this in a generic way.
We should do a similar migration all over pySim (pySim-shell,
filesystem, etc.) - but for now only do it in the low-hanging fruit of
pySim-trace aka pySim.apdu
Change-Id: I0cde40b2db08b4db9c10c1ece9ca6fdd42aa9154
87b4f99a90