Fix typo.
Fix typo in README.zh_CN.md.
Merge pull request #5 from Shanicky/master

Fix typo.
Update description for `ignore_case` in doc.
Judging by the possible values of `ignore_case`,  this config variable should be a `switch` in stead of a `switcher`.
Merge pull request #7 from XuKaiqiang/master

Update description for `ignore_case` in doc.