Emacs highlighting annoyances

[sawyl]

Been bugged by the way that Emacs on Aqua highlights expressions for a while. For some reason, probably related to feng shui, it seemed to feel compelled to use white on white to highlight completed expressions making it totally impossible to tell which bit of lisp was about to be eval-ed. Turns out the trick to fixing it is change the face paren-face-match-light (or presumably -dark) rather than mess around with the paren group settings.