This allows DataList::create('SiteTree') as equivalent to Object::create('DataList', 'SiteTree'), without
having to have a create() function on DataList. Required for E_STRICT compliance.
DBField::prepValueForDB() and StringField::prepValueForDB() to ensure
the field value is escaped correctly for the database. This means
databases like MSSQL can introduce an "N" prefix (marking text as
unicode to be saved correctly) by overloading the
prepStringForDB method. MySQL, PostgreSQL and SQLite3
operate as usual.