changed link style in thoughts

Replaced italics with underline, and replaced underline on hover with a color change. Currently, if someone's color blind of the variety where they can't see red, links could just look like regular italicized text. And I used an underline instead of the dotted border-bottom of the others because it looks weird to have a line that low all the time, instead of just on hover.

Working sample: http://tpbp.katywatkins.com/