Improvements:
- 雄 is now _xióng_ (previously _yóng_)
- 茝 is now _chǎi_ (previously _chǐ_)
- 銳 is now _ruì_ (previously same as 衛)
- 佳韻開口牙喉音 is _ie_ by default
  - （Temporary solution) _ai_ for 影溪母, _ia_ for 疑母 by default
- (Temporary solution) 尤韻脣音 (excluding 明母) is _u_ by default
  - 明母尤韻 is derived as 侯韻 (result same as before)
- 幽韻明母 is _miu_ (previously _miao_)
- 梗攝莊組三等 is derived as _-e_ (previously _-i_)

There are several places left for further improvements (chiefly
regarding some minor cases and the 白讀 system), annotated with TODO and
FIXME.

Other improvements:
- 雄 is now _hung4_ (previously _jung4_)

Fixes nk2028#75