Added default value. Added support for an unlimited number of arguments. Better phpDoc.
Better phpDoc
Renamed argument of the method "where". Better phpDoc.
Added support for an unlimited number of arguments of the method "groupBy". Better phpDoc.
Renamed argument of the method "having". Added support for an unlimited number of arguments. Better phpDoc.
Added support for an unlimited number of arguments of the method "orderBy". Better phpDoc.
Better phpDoc for the methods "limit" and "offset".
Better phpDoc for the method "execute", "getQuery", "alias", "set", "addCommand" and "export".
Better phpDoc for the methods "update", "insert", "delete".
Fixed bug joining separators.