The cleanup of notes resulting from input by site reviewers last year resulted in many <note>s being reduced to a single word, which is often a simple correction for the word or phrase being annotated. Such cases are not actually <note>s at all; they're better represented by <choice>/<sic>/<corr>, in the same way as we already use <choice>/<orig>/<reg>. Noticing this, we also noticed that the <mentioned> tag has been rather misused in some cases, when either <quote>, <soCalled> or nothing at all would be more appropriate. I've also added a handler for <choice>/<sic>/<corr> which is parallel with the existing one for <choice>/<orig>/<reg>

I've worked through the Sonnet 1609 text to change all such <note>s to <choice>/<sic>/<corr>; some should be <choice>/<orig>/<reg>, but I can't determine that, so LSPW will make another pass through the file and fix those. This markup can then be used as a model where similar situations pertain in other files.