Small BooleanPropertyComponent LookAndFeel annoyance/bug

Jules, A small bug:

BooleanPropertyComponent currently contains a paint method which by default fills it with white, meaning the BooleanPropertyComponent
 will need to be subclassed if a white background is not desirable.

A small annoyance, but still...

I think the "correct" behaviour is that it draws no background at all, alternatively that it uses PropertyComponent::backgroundColourId, or some other colour that can be set outside of the BooleanPropertyComponent class...



Good call - I've added some new colour IDs for that.

Thanks! :)