0.16.0

Changes since 0.15.0:

• Add Python 3.9 wheels
• Drop Python 3.5 support
• Expose camera-defined per-channel white level (#122)
• Expose libraw X3FTOOLS and 6BY9RPI feature flags (#124)
• Fix raw_pattern for black and white images (#123)
• Update LibRaw from 0.20.0 to 0.20.2 (#125)
• Update libjasper from 2.0.19 to 2.0.22 (#125)
• Update liblcms2 from 2.9 to 2.11 (#125)