added TransactionQuery
added BeginTransaction, fixed ctors.
added CommitTransaction.
added DDLQuery.
added CreateQuery.
added DropQuery.
added AlterQuery.
added DMLQuery.
added Delete
added Update.
added Select.
added ManagementQuery.
added Grant.
added Revoke.
directory cleanup.
added Script.
added Comment.
refactored.
added SqlQuery test suite.
refactored to used a common test driver