Surfacing a "unique identifier" for all FF

[acbart]

We need a "unique identifier" for FF that is viewable by humans. For many of these, it will be their arguments (e.g., ensure_function("banana") would be able to use the "banana" argument as its unique identifier). But for example unit tests, that will need to be based on the function being called and it's arguments.

Not sure about about TIFA and its hodge-podge of things, need to think about that more. Take the unused_variable example - obviously the name of the variable, but what else uniquely identifies things? It's location?

[acbart]

Going with the name specifier. This is such a big change, and the timing is right, I'm going to use this to release Pedal 3.0! I've got basic logic for runtime assertions and part of static assertions (with a pretty clear path for them). Still need to figure out exactly how to handle user input for runtime assertions, and all of the TIFA and CAIT stuff still needs work.