It do't support the chinese coding

[jiahut]

For example

cat test.md

# issues

## 紧急bug

md_to_json test.md

{
  "issues": {
    "\u7d27\u6025bug": ""
  }
}

hope it should be:

{
  "issues": {
    "紧急bug": ""
  }
}

[njvack]

Wow, I left this for a long time. This is almost certainly a duplicate of #1, assuming your data is in UTF-8 to begin with.

I don't currently have time to fix this; however there's a proposed fix in that issue and I'll give it a try sometime soon.