Termination Criterion and PageRank for the new Java API
Optimization of SimplePagerank, setting of a correct serializer for the termination criterion, empty implementation of combiners for cogroup
Add utility result verification method for K/V pairs with double value and delta threshold.
Allow bulk iteration termination criterion with different data type than partial solution
Cleaned up page rank example and adjusted tests
Add getSolutionSet() and .getWorkset() for delta iterations

Before, the result of dataset.iterateDelta() would be the workset and
the solution set could be obtained via iteration.getSolutionSet().

This is confusing since you are not told what the result of
.iterateDelta() is supposed to be. Now, when using the result an
exception is thrown during pre-flight that advises the user to use
the two methods to get the correct dataset (work, solution).