Use the Rust logging so that normal messaging isn't overwhelmed by
messages printed. The default level is 'error' which will only print
full errors (including the failures at the end).
To run with warnings:
RUST_LOG=warn ./target/release/bootsim ...
This will print warnings, showing the particular failures in mind.
Using 'info' instead of 'warn' will print lots of progress as it runs.
'sim' is a small simulator for the bootloader's update code. It tests
untimely powerdowns to ensure that the bootloader will recover from a
power loss or reset at any time during the boot.
Note that, as of this commit, there are some failures in the test that
need to be investigated.
Also note that this build script does not output proper dependencies for
source files outside of the simulator directory, and won't rebuild the C
files if they or headers are modified.