[Feature request] A setting to add words to the syntax highlighter

I develop in C and would really like syntax highlighting for my typedefs for ``uint32_t``, ``uint64_t``, ..., such as ``u32``. It could be a setting in the config file and here is a suggestion for how it could look like:
```
[[style]]

[c syntax highlight addons]

type_keywords: u8, u16, u32, u64, ...
value_keywords: ...
modifiers_keywords: ...

[cpp syntax highlight addons]
...
```