Added support for @CompositeTimed annotation

[alex859]

It can be sometimes useful having different timers on a method to avoid failing events to falsify the overall timing statistics.
The @CompositeTimed annotation adds 3 timers on a method call:

• a failure timer that tracks the duration of the method when an exception occurs
• a success timer for methods calls that end successfully
• an overall timer

@CompositeTimed(name="compositeMethod", failedSuffix = "Fail", successSuffix = "Success", absolute = true)
public void compositeTimedMethod() throws Exception
{
    ....
}

will create compositeMethod, compositeMethodSuccess and compositeMethodFail timers.

Hope this can help.