2.2.1

Release Nageru and Futatabi 2.2.1.

  - Work around an issue with OpenGL on Wayland, causing all
    displays to be blank.

  - Several fixes related to video inputs; in particular:
    - Fix crashes when the master clock goes faster than 60 Hz
      (which could happen primarily if an SRT input is the master).
    - Be more resilient to errors in hardware video decoding
      when the stream starts out broken (e.g., not on a key frame)
      but recovers.
    - Multiple fixes related to hardware acceleration on nVidia.
    - Incoming frames of too high resolution (larger than 8 MB)
      will be refused instead of crashing. Such videos may be
      supported better in the future.