Merge pull request #2222 from boggle/2.1-cypher-heuristics

Using heuristics in cypher for all nodes and label cardinalities
Renamed some Cypher tests so that they actually get run by maven
Changed HeuristicsService interface to single heuristics() method returning HeuristicsData

o Fix equality and hashCode for heuristics data containers
o HeuristicsDataCollector => HeuristicsCollector
o Introduced RollingAverage.Parameters
Remove unnecessary check for file path existence
Change cost and cardinality metrics to always return Double
Renamed methods in GraphHeuristics API
Change tests so that the heuristics can be mocked easily