Log Message:
Update to 3.53. From the changelog:

- fixed out-of-range exception with repeated `AddKeyword` calls
- added `KeywordFormatHints`, `Priority` and `Constraints` elements to
  syntax definitions
- added Lua function `AddPersistentState`
  (https://gitlab.com/saalen/highlight/issues/112)
- renamed md.lang to markdown.lang
- added Fish syntax definition (thanks to James Lee)
- makefile: added _FILE_OFFSET_BITS=64 flag
- CLI: added optional fallback syntax to `--force`
  (https://gitlab.com/saalen/highlight/issues/126)
- CLI: added option `--max-size`
  (https://gitlab.com/saalen/highlight/issues/127)
- GUI: added multibyte path trace window
- GUI: fixed superflouos creation of the same stylesheet file