Use short-paths in values

[yminsky]

Right now, short-paths applies only to types, not to values printed out by the toplevel. This leads to odd examples like the following.

If we could get the new version of short-paths in and apply it here, it would clean up the output in a number of places. (The above example should likely be fixed in a different way, by putting the s-expression pretty printer in place. But it's still a good example.)