Weekly pre-release

Improvements

• speed 10 is overall 30% faster and the quality is slightly improved

• The quality is improved for all the other speed levels, but with larger encoding times e.g.:
  speed 4 is 5% slower

• About 50% smaller binaries

• About 14% faster build time

New feature

• Switch frame support (use -S, --switch-frame-interval <SWITCH_FRAME_INTERVAL> to enable it from the CLI)

Changes

• The C header produced is now C++-compatible