Implementing DataRepresentation and Pairwise Comparison

[LukeANewton]

These objects encapsulate two functionalities of the system, parsing test cases into the system and performing pairwise comparisons. The DataRepresentation class performs the functionality for parsing test cases. The DataRepresentation and PairwiseComparison together provide functionality for perfoming pairwise comparisons.

This task contains a number of files:
DataRepresentation: an interface for concrete data representation classes to implement
CSV: an implementation of DataRepresentation for comma separated values
PairwiseComaprisonStrategy: an interface for pairwise comparisons to implement
JaccardIndex: an implementation of a PairwiseComparisonStrategy
CommonElements: another implementation of a PairwiseComparisonStrategy
Capstone: contains a main file to run some tests on the above files (part of a test driver along with FileReader)
FileReader: an INCOMPLETE version of the file reader that will be used in the system (part of a test driver along with Capstone)

[LukeANewton]

This can be tested, the code is on master branch.

The classes to test are:
DataRepresentation and CSV from the data_representation package

CommonElements, JaccardIndex, PairwiseComparisonStrategy, and TestCaseFormatMismatchExcpetion from metrics/comparison package

[CameronRushton]

I'll test