Provide separate default colors for light and dark backgrounds.
Just tweak comments.
Merge branch 'master' of github.com:greghendershott/racket-mode

* 'master' of github.com:greghendershott/racket-mode:
  Set paren-face to default foreground face.
  Changed parenface from honeydew4 to gray30.
Better comment
Indent for/fold and for*/fold correctly. Closes #2.