Added IntIntMapTest and minor improvments

Added new IntIntMapTest to compare values with radargun benchmark.

Added new methods to KeyUtils.java for Integer keys.

Added new method addOperationRemainingProbability() to OperationSelector.java to add an operation which consumes the remaining probability.

Cleanup of bash scripts: update-stabilizer makes now use of $STABILIZER_HOME if set and uses maven to determine stabilizer version.
Just PUT and SET, for GET there is a distinct probe. For what I wanted to do with the test PUT and SET would be used exclusionary to compare the performance between them.