6.1.0
fix: Enable axis statistics to be able to register -- exclude if unnecessary for code size.
chore: (1) Shift all pure function handlers (legacy pattern) to stage handler to remove unnecessary throw and catch - better for debug; (2) sunburst did not use dataFilter in correct way and it did not work, therefore remove it.
fix regression: (1) Revert the recent change to zlevelKey for backward compatibility. (2) Add guard to progressive block.