Add a test script to simulate fpscan.
Remove trash.
pep8.
Clean up, reorder definitions.
Remove trash.
Add background cmd to run fpscan.
Use `super` instead of old-style init.
Test basic fpscan detections.
Let FPScanCommand accept params.
Write error message to stderr.
Safety belt.
Write fail messages to stderr.
Look like 'fail' message goes to stdout.
Add tests for (emulated) scans.
Save result to known location.
Mimic also comparison functionality.
Test fingerprint comparison functions.
Make BackgroundCommand API more useful.
pep8.
Fix scan functions.