Corrected OCR errors and added one speaker tag in Terence, Andria (Latin).

Latin version of Terence still has many OCR errors; in Andria, I collated the text with St John Parry's edition (on archive.org), partly using Latin spellchecker, partly reading. Ter. Andr. 423 was missing a tag for a speaker change. In the process I am also learning git, so there are some duplicate commits and messages; commits e81b9c6 and 93a49a2 bring the essential changes together.