Greaseweazle Tools v0.37

Release Notes:

• Require Python >= v3.7 (ignore this for Windows binary builds)
• Logging output to stderr is now buffered no more than per-line
• HFE: Auto-detect output bitrate if possible, else require on command line
• gw convert: Fix crash when printing summary information
• gw convert: Fix --tracks= handling to respect step= and hswap
• gw convert: New option --out-tracks to allow step= and hswap override
• D81 (commodore.1581): Fix sector header H field: should be swapped