Fixed XML well-formedness errors I introduced and resolved entities.
Fixed XML well-formedness errors I introduced and resolved entities.

oreillymedia/HTMLBook,oreillymedia/HTMLBook,mushroomgithub/HTMLBook,gitenberg-dev/HTMLBook,macmillanpublishers/HTMLBook,macmillanpublishers/HTMLBook,wastemobile/HTMLBook,wastemobile/HTMLBook,macmillanpublishers/HTMLBook,gitenberg-dev/HTMLBook,oreillymedia/HTMLBook,mushroomgithub/HTMLBook,mushroomgithub/HTMLBook,gitenberg-dev/HTMLBook