XD-7 - Tuple data structure
The initial commit was designed to be backwards compatible with Spring Batch's FieldSet class.  Some differences, it does allow for non-String values and conversions from Strings to rich types are done through Spring ConversionService.  There are several TODOs in the code that need to be revisted on a subsquent iteration.  Some open questions are handling of null and default values.  Test code from Spring Batch's was ported over to help ensure backwards compatibility.
XD-7 - Tuple data structure
Change to use primitive types instead of Wrapper types for byte, short, int, long, float, double, char and boolean.  This avoid NPE from when doing int i = tuple.getInt("fieldWithNullValue").  Non primitive types will return null (BigDecimal, Date, String)
XD-7 - Tuple data structure
Add getters for primitive types that take default values.