Add `raise-argument-error', `raise-result-error', `raise-arguments-error',
and `raise-range-error'.
The old convention was designed for reporting on a single (sometimes very
long line). The new convention is
<name>: <short message>
<field>: <detail>
...
If <detail> is long or itself spans multiple lines, then it may
also use the form
<field>:
<detail>
where each line of <detail> is indented by 3 spaces.
Backtrace information is shown as a multi-line "context" field.
original commit: 9e7548de615610a5be2adb33c4cf6ee10f9e7589
Also commented out some tests of reflective operations on contracted objects.
I've added a note that describes how we might be able to fix this, if
we decide it's worth doing.
original commit: 30afcd3bf5cc272f1642449989628024bedc41eb
