Conditional Unique Column Combination

Merge the fork for CUCC into the main metanome branch. 

Metanome is now able to execute CUCC algorithm. This includes:
- creation of ConditionalUniqueColumnCombination as result and associated result receiver and algorithm classes
- creation of ColumnCondition as part of ConditionalUniqueColumnCombination
- integration into AlgorithmPage and ResultTablePage
- creation of CUCC example algorithm
- additional methods in PLIBuilder and PositionListIndex that are required by the algorithm

move long description to general method doc entry