3274 - test framework bugfix

Otherwise failures of (~be x y) print nonsense like:
  got: 34
  expected: 34

Still kinda ugly and hard to parse in most cases.
3275 - verbosely show matcher only if necessary
3276
3277
3278 - list comparison

Experimental; we're supporting nil at the cost of breaking range
comparisons: http://arclanguage.org/item?id=18136
3279 - now comparisons need to handle nil
3280 - bugfix in ripple incomplete_eval

Do we need a new trace label here?