add named colors for positive (usually green)
neutral(usually yellow) negative(usually red)
foreground objects, such as text or parts of
svg icons/themes
REVIEW:127696
Change-Id: I646306339f1684cdc062da3d3af1489af6092372
we have a color in the Plasma theme "highlight" that is basically
an accent color used around.. but one of the uses is to use it as
a background, such as highlighted text. in that case we don't know
what color would be safe for contrasting on top of it for things
like the highlighted text color (plasma style used the background
color for that, which is incorrect)
REVIEW:127637
