v0.9.0

Changelog

• 7dd69d7 Emission clusters, -version dirty once, doc fixes
• 94274be Full-tree review fixes: YAML documents, upper-air bounds, AOD cap
• f92c55a Regenerate default.pgo and demo.jpg
• 93083a8 Review fixes: empty -targets, fall-back clocks, underground levels
• 30005c8 Upper-air seeing estimate, rain gate, and review fixes
• 5b6a1e9 astro: Window skips the previous night's tail at a dark noon
• d63f683 test: mutation tests, written blind to the existing suite
• c4a65a7 test: tighter SOFA limits; fix go fix loop in weather mutation tests
• 3654601 web: Copy link button