Card & BannerImage rework

Someone suggested splitting my original branch into multiple branches, so here it is.

• BannerImage
  • extra properties for customizing title heading
  • title background can now expand to fill the entire space if non-covered space is too small
  • updated doc
  • animate border radius. This fixes visual problems when expanding or shrinking (if it is enabled)
• Card
  • expose actions alignment (Card)
  • update doc

MR DEP: !592, because of BannerImage expanding out of the card at the top when the card has very little width.