#19 Limit values stored in data file

[Michael hall]

The datafile right now is quite large, saving anything
that can be taken out of a get method, and contains
mostly useless data. Usually only id and value are
necessary, but we can't limit to only those.

Try using Java 1.5 annotations to let the SurveyObjects
themselves specify which methods return a value that
should be stored as data. This would have the added
benefit of allowing an object to declare non-get
methods as something that returns data that should be
stored. It would also allow us to use objects as
return types.

Something like @DataPoint that is limited to Methods
and available at Runtime.