Feature request: `row_names`/`header` highlighter

[thchr]

It'd be neat if highlighting could be defined for the data supplied in the header and row_names keyword arguments. At present, the only way to achieve this is to put the row/column labels into the table itself (since highlighting is only possible for the table data), which is of course not ideal.

[ronisbr]

Hi @thchr

I confess I never thought this would be useful. That's why I didn't implement. However, since you are saying this is useful for you, I will do, it is very easy. I just need to take care now that we reach v1.0 to not break anything :D