ADDED: Snapshot.cs;

 - Object to marshall data for a price update

ADDED: MarketPriceHistoryDAL.cs;
 - DAL for table for prices.

CHANGED: MarketPriceLevel.cs;
 - Added GetTotalQty() to sum all lots on a level, for pricing.

CHANGED: Market.cs;
 - Added Close() logic to drop DAY orders on close.
 - Price member variables added with accessors, and Snapshot accessor.
 - Added Price(), getPrices(), to create snapshot.
 - Removed SeqNumMatch, not used.
 - Comments removed.

CHANGED: OrderContainers.cs;
 - Added StopsContainer::GetAllDayOrders(), for dropping of day orders.
 - Added WorkingContainer::GetAllDayOrders(), as above.
 - Added WorkingContainer::GetJsonSnapshot(), for pricing.

CHANGED: Order.cs;
 - Added IsDAY() and IsGTC() bool check functions.

CHANGED: OrderQInDAL.cs;
 - Select statement now more defensive against Deleted orders.

CHANGED: TableCreateScript.SQL (both versions)
 - MarketPrice table removed, redundant.
 - MarketPriceHistory columns renamed to match Snapshot object type.