dump1090-mutability (1.10.3010.14mu-12)

• Add generation of history JSON.
• Load history when the webmap is initialized.
• Display stats on exit in --net-only mode.
• Explicitly pick the closest tuner gain to the one requested.
• Include a status message in HTTP response headers.
• Fix sort-by-message-count in the webmap.
• Always sort missing values at the end of the table, even in a descending sort.
• Avoid a (rare) divide-by-zero crash in 2MHz --phase-enhance.
• Try to work around a libusb crash on exit after SIGINT.