grafx - Extensible Java Graphics Package Code

One more little optimization plus a comment improvement in CoveredHoleMetric.

Defining m_holeCountsByLayer in CoveredHoleMetric. Saving that object as
member to avoid excessive instantiations.

In the process of optimizing CoveredHoleMetric. Keeping objects
m_sqrtEdgesCornersWeightsCache and m_coveredHoles as members instead of
instantiating every time.

Comment formatting in AlternateNoChildLeftBehindMetric.

Optimizing QuadraticBowlMetric by caching elevations.

Optimizing LinearBowlMetric by caching elevations.

Optimizing QuadraticNookAndCrannyMetric a bit more by caching elevations.

Optimizing LinearNookAndCrannyMetric a bit more by caching elevations.

Optimizing HeightFluctuationMetric some more.

Optimizing AlternateNoChildLeftBehindMetric.