adm::CompareRtimeDurationLess broken since Time format update

[rsjbailey]

The Rtime and Duration Comparator currently fails to compile if used:

libadm/include/adm/utilities/comparator.hpp

Lines 63 to 78 in 1f3e87d

	struct CompareRtimeDurationLess {
	template <typename AudioBlockFormat>
	bool operator()(const AudioBlockFormat& lhs, const AudioBlockFormat& rhs) {
	if (lhs.template has<Rtime>() && rhs.template has<Rtime>()) {
	if (lhs.template get<Rtime>() == rhs.template get<Rtime>()) {
	if (lhs.template has<Duration>() && rhs.template has<Duration>()) {
	return lhs.template get<Duration>() < rhs.template get<Duration>();
	}
	}
	return lhs.template get<Rtime>() < rhs.template get<Rtime>();
	}
	return false;
	}
	};

This tries to compare two adm::Duration objects and two adm::Rtime objects. These are both NamedTypes containing adm::Time. Neither has an operator< comparison operation defined, so attempting to use the comparator fails.

I assume the templated call operator isn't instantiated anywhere, which is why the build succeeds.