added classes for Target Data
added IOData classes
added qualityData
Added AbsenteeismData
fixed minor compile errors due to changeover
fixed bug caused by adding type parameter to DataType by renaming it to ImplementedDataType

The original DataType class was re-added to give access to the key methods for external classes.
finally resolved all build problems caused by removing DateOption

I should add that DateOption was no longer in use due to the date being split up into day month and year fields
changed production days and order quantity to mergeable doubles
Changed DataField to match new classes