remove y18n

[gucong3000]

Remove dependence of y18n

[codecov]

Codecov Report

Merging #109 into master will increase coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master     #109      +/-   ##
==========================================
+ Coverage   99.65%   99.65%   +<.01%     
==========================================
  Files          13       13              
  Lines         576      581       +5     
  Branches      116      117       +1     
==========================================
+ Hits          574      579       +5     
  Partials        2        2

Impacted Files	Coverage Δ
lib/editor-config-error.ts	94.11% <100%> (+0.36%)	⬆️
lib/rules/end_of_line.ts	100% <100%> (ø)	⬆️
lib/rules/charset.ts	100% <100%> (ø)	⬆️
lib/rules/insert_final_newline.ts	100% <100%> (ø)	⬆️
lib/rules/max_line_length.ts	100% <100%> (ø)	⬆️
lib/rules/trim_trailing_whitespace.ts	100% <100%> (ø)	⬆️
lib/i18n.ts	100% <100%> (ø)	⬆️
lib/rules/indent_size.ts	100% <100%> (ø)	⬆️
lib/rules/indent_style.ts	100% <100%> (ø)	⬆️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 4bf2a74...b5d9d80. Read the comment docs.

[gucong3000]

Related: yargs/y18n#55