Changed spssreader version
Made sure that the identifier values are properly formatted and typed by using the SpssVariableValueFactory
Merge pull request #15 from kazoompa/bug-spssreader

Changed spssreader version
SpssValueTable disposable so that upon destruction, its SSPSFile gets closed.
Merge pull request #16 from kazoompa/bug-spssreader

SpssValueTable disposable so that upon destruction, its SSPSFile gets cl...