Text alignment in Free Text annotations

I've been looking through the API, but I can't seem to find any way to set the text alignment for free text annotations. Looking at the PDF spec, I believe this is supported as rich text strings support that (correct me if I'm wrong). Is this something that can be added? At the moment, the only way for me to support text alignment is to write out the text to a content stream (but then I can't find a way to edit the text later).

On a side note, I also can't find any way to style the text to make it italic or bold. Is this also something that can be added?

Thanks,
Mike