CardBody: provide hasNoPadding property to remove body padding

[KKoukiou]

In Cockpit we use everywhere card, but when these contain list we decided that it's too much wasted space to have the padding in the card body. So we remove it. It looks like this:

Would you be interested to expose a property to do that properly?

[tlabaj]

cc @mcoker @mceledonia

[mcoker]

@KKoukiou you can omit <CardBody> to use a card without padding - would that work?

  <Card>
    This card has no padding
  </Card>

[KKoukiou]

@mcoker Sure :) I actually had noticed that but did not want to use it because the demos don't have such an example so I though it was not a valid usage. So since you agree that this is a valid usage, we don't need extra implementation.