feature: add preliminary support for CJK languages

[f0rb1d]

This commit adds preliminary support for CJK languages.

To be specific, the original library would always output '1 minute' of reading for CJK languages. This commit fixes the issue, and more tests are on the way.

[Josh-Cena]

By my understanding, a lot of characters between U+2E80 (0d11905) and U+4A37 (0d18999) are CJK as well, and the characters between U+A0000 (0d40960) and U+ABE0 (0d44000) do not look very CJK. Any rationale behind using the particular interval U+4A38 ~ U+ABE0?

You may consult the complete Unicode block on the Wikipedia page, if it helps.

The current version already works well for a typical CJK paragraph. I was just about to do the same thing before I saw your PR :P

[Josh-Cena]

@f0rb1d Are you going to continue working on this? I'm looking forward to this feature 👀

[f0rb1d]

@Josh-Cena Sorry I've been offline for a while, and I kinda forgot this stuff. It looks like you've done a much greater job than I did, so I would close this PR and help you finish yours. Let's discuss under #35.