Workarounds for windows

- clear screen commands are different ('cls' vs 'clear')
- add test for win platform. Not sure how reliable it is...
Visual improvements, windows & light/dark terminal acommodations

- color adjustments to suit light and dark terminal scheme
- only cards use a hard background color.
- note: win console draws black text as gray and white bg as light gray
- card improvement: draw suits in the corners like real cards
- win users will prob see chars instead of suit symbols