More updates for issue #125.

- Removed HouseStat classes and their usage from all games
- Removed saveGameStats() and loadGameStats() from all games
- Added migration of Blackjack house stats for "migrate" command
- Added "shoe_size" and "num_cards_left" to the BJRound table definition
- Removed loadGameStats() as an abstract method for CardGame
- Added loadDBHouse() and loadDBGameStats() for Blackjack
- Moved showPlayer() stat methods back to CardGame updated with data
  retrieval from DB (Overriding also updated in TexasTourney)
- Updated strlib.txt
- Added loadDBGameTotals() method to all games and removed
  getTotalPlayers()
- Updated showPlayerRank() method for all games to use DB
- Fixed get() for players when "winrate" is supplied as the key