* Fix#588, Ideographic characters should be grouped together.
Following the suggestion of using regex to find the ideographic
range in this SO answer https://stackoverflow.com/a/2718203/554903
We group the ideographic characters together, while keeping other
chinese, japanese and korean characters apart.
* cleanup
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Co-authored-by: Sascha Ißbrücker <sascha.issbruecker@gmail.com>
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