Fixing dispatching of indexed parameter req

[notthetup]

This is a fix for ParameterMessageBehavior when setting indexed parameters. When an Agent has a defined setter method setMyParam(int ndx, Object value), the ParameterMessageBehavior can't find the method.

I traced this down to Apache Commons Lang. ParameterMessageBehavior calls invokeCompatibleSetter which then calls MethodUtils.invokeMethod(agent, name, ndx, value), where name is the method name (setMyParam in our example), ndx is the parameter index and value is the value to be set.

While doing the reflection MethodUtils does a ClassUtils.toClass(args) on the list of all args. That converts the int ndx into a boxed Integer. Because of this, looks ups of indexed setters can fail since they're commonly defined with the index being an int.

This fix tries to detect that and tries to use the standard Java reflection API (Class.getMethod) to find an appropriate method to dispatch to.