This commit adds tooling to find potential issues with code
that are difficult to notice during debugging (especially on
builds from the CI which lack debugging capabilities).
File manager supports basic operations like browsing files,
renaming, copying and removing
Snapshots allow to take a snapshot of current app data, and
compare to it later on with basic hexdump view - useful to
notice anomalies or modifications to files that shouldn't
be accessed.
File watcher checks for file modifications in real time, which
is used to see what actions are happening to the fs in real
time.
Fuzzing can be used to load/create wallets randomly to see
if any of them will get corrupted (can be used in addition
with wallet_fuzzer.sh script that kills the app and restarts
the process at random intervals to simulate unexpected action
that can happen for example in the background).
In addition I've added toString method to {bitcoin,monero,nano
,zano}_wallet_keys.dart so I can easily compare the results
when fuzzing without accessing wallet-specific code.
