### What problem does this PR solve?
Edit chunk shall update instead of insert it. Close#3679
### Type of change
- [x] Bug Fix (non-breaking change which fixes an issue)
### What problem does this PR solve?
Always open text file for write with UTF-8. Close#932
### Type of change
- [x] Bug Fix (non-breaking change which fixes an issue)
### What problem does this PR solve?
- Update readme
- Add license
### Type of change
- [x] Documentation Update
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Signed-off-by: Jin Hai <haijin.chn@gmail.com>