ISSUE-132: FURTHER INVESTIGATION: An example showing use of Media fragment URI to refer to portions of a signal

Discussed during June 14 call. This originally came from the Emotion subgroup. Would be fairly straightforward to add an example. This is just an extension of using emma:signal. You would allow signal to have fragment URI's and allow signal within application semantics, or do we have something else, reserving "signal" for the whole signal. Could have a group with classifications of different parts of the utterance. Or a space-separated list of fragment URI's. Could be useful for annotating audio or video. Could we just borrow something from the EmotionML spec?

Discussed during June 21 call.
We are starting to think that you should use emma:group rather than trying to fill individual parts of a signal, just use group with fragment URI, you don't have to distinguish between a full file or a portion of the file.