Allow participant lifecycle methods to be declared private

Currently following lifecycle method (and any other that is declared private) will never be invoked:

@Compensate
private void cancelOrder()
{
  ...
}

This is because it is declared private and thus never seen by the reflection mechanism.

The improvement is to have private methods also considered when searching for lifecycle methods. public methods will always be found, even if they are present in a super class. However, private methods in the super class can not be found.