Various test fixes:
Hql/Ast/HqlFixture.UnaryMinusBeforeParenthesesHandledCorrectly():
    Don't depend on temp tables.
Stateless/StatelessSessionFixture.cs:
    Allow for dialects that don't have fractional seconds in timestamp versions.
sqlServerCe/NHibernate.Test.last-results.xml:
    Allow UnaryMinusBeforeParenthesesHandledCorrectly() to fail (rest of the suite
    does) due to lack of Date support in dialect. Already fixed on master.