Label are forced in gray -> unreadable againts dark background

[zartc]

Bootstrap v2.0.3
On line 771 the color of the <label> tag is forced to #333333 (some kind of gray). I don't know if it is intentional but it is unfortunate because it makes labels unreadable when displayed against a dark background.

[mdo]

All our text will be like that unless you specify an override.

That said, I did notice that the label had the font color declared again, so I've removed that in 2.0.4-wip.