use InitOnOff
add blacklist
add dict/readme.md
ci
add filter singword in keywordextractor.
add changelog.md
modify readme.md
add test/keyword_demo.cpp
modify test for keywordextractor
fix bug: cmp function pair<string, uint> -> pair<string, double>
fix bug: cmp function pair<string, uint> -> pair<string, double>
add keyword_demo into readme.md