fix(Range): rename locate to located

[favonia]

While finalizing the debugging interface, I noticed that the Range.locate is taking a location to create an element of located, not locating an element. I'd like to fix this API naming.

Old name	New name	Typical usage
Range.locate	Range.located	located loc term
Range.locate_opt	Range.located_opt	located_opt loc term where loc can be None
Range.locate_lex	Range.located_lex	located_lex $loc term (in Menhir)

I'm not sure if located_lex is the best name, but locate_lex seems wrong.

[mikeshulman]

Are you saying that "giving a location to an element" shouldn't be described as "locating an element"?

[favonia]

@mikeshulman I thought "locate" means "finding the location of something when we don't know where it is", but in this case the location is explicitly given. I'm not insistent on this PR if native speakers feel otherwise.

[mikeshulman]

In Merriam-Webster, the first definition of the transitive "locate" is "to determine or indicate the place, site, or limits of", but the second is "to set or establish in a particular spot". So I think this use of "locate" is justifiable.

[favonia]

@mikeshulman Got it. Abandoning this PR now.