Updated gradle build scripts so there is a separate benchmarks task
Updated ObservableBenchmark to follow better benchmarking practices
Merge pull request #963 from gvsmirnov/master

A more robust JMH benchmarking set-up
SubjectSubscriptionManager fix.
Merge pull request #964 from akarnokd/SubjectSubscriptionManagerFix

SubjectSubscriptionManager fix.
Version 0.17.1