Improve configuration file comments

[squigglezworth]

Per #31

Improve configuration file comments to better illustrate what color title and color title-bold refer to (i.e., the former refers to the right-hand volume display and screen list names, and the latter the left-hand title)

On this topic, why do the screen list names use color title and the name prefixes use color title-bold? This seems randomly inconsistent to me. I'd recommend a setting for the screen list information and title, and a separate for the volume indicator