Ahodges/documentation/for662

Added procedures for adding posts, responses, and comments in discussion topics on the Discussion page and in the courseware. Also added contextual information ("Anatomy") for students.
forum, you can check out the introductory Anatomy section. (The chapter contains this section whether or not someone has previously participated in an online discussion forum.) Also, capitalize "Anatomy" and make the word a link to that section (see the formatting cheat sheet for instructions).