added basic weighting of sources to Fusion operator
fixed MostFrequentResolution, added MostFrequentResolutionTest, some refactoring
Merge pull request #3 from fatschi/master

scrub operator and first fusion operator implementations
Refactored DD
Merge branch 'master' of github.com:AHeise/sopremo-cleansing
renamed all XxxRule to XxxConstraint (renamed tests accordingly), added annotation (SingleOutputResolution) to allow the specification of resolutions that will always result in a single value, implemented stub for warning when last resolution isn't a SingleOutputResolution to enable the user to review there written code