Add support for mcdoc file

[SPGoding]

mcdoc era

Specification for mcdoc can be found here.

Check list:

• [x] Parser.
• [x] Colorizer.
• [ ] Type checker.
• [ ] Completer.
• [ ] Formatter.

nbtdoc era

Specification for nbtdoc written by Yurihaia could be found here.

Check list:

• [x] Parser (#839).
• [x] Colorizer (#848).
• [x] Type checker (#847).
• [ ] ~~Completer.~~
• [ ] ~~Formatter.~~