Add the possibility to add an instance of Termination to the TerminationConfig

The TerminationConfig class doesn't allow the user to sets a custom instance of a Termination. The only function available is to sets a Termination class using TerminationConfig.setTerminationClass(Class<Termination>). The user is then limited to provide a custom termination class that doesn't required any settings. (i.e.: it's not possible to have a Termination with a constructor requiring arguments)

I suggest to add a function similar to other configuration class. e.g.: TerminationConfig.setTermination(Termination) and TerminationConfig.getTermination()