Please provide an "empty templateLoader", by analogy with the "empty UIOptions", so that people who don't want the default panels don't have to deal with fetching nonexistent templates or figuring out how to configure them away. Please also add an implementation comment explaining that this is one of the two remaining undesirable points of dependency (the other being the mapOptions definition) which prevent panels from being completely self-contained - ideally a panel should be able to define its own template URL, but it can't - this will be resolved by http://issues.fluidproject.org/browse/FLUID-4982