Implement Speed4j within Hector API

Hector uses Speed4j to display performance metrics.

Speed4j, a very simple (but fast) Java performance analysis library. It is designed using Perf4j as a model, but hopefully avoiding the pitfalls inherent in Perf4j's design. Speed4j has a dependency on SLF4J (see http://slf4j.org), which it uses to log its workings, but no other dependencies.

reference: http://rantav.github.com/hector/build/html/content/speed4j.html#how-to-enable-speed4j