refactor out Simple backend, leave only api methods in pinyin.rb
refactor tests
add mmseg backend
update license
finish mmseg backend
fix mmseg on empty string
fix abbr with mmseg backend
add more regression tests for polyphone
move data files
bump to 0.3.0
add polypone example
update README
add a polypone test
add rmmseg-cpp as runtime dependency
remove old data
update data
update README
update README
regenerate data, include polyphnetic data
move #to_ascii to PinYin::Util