jsc-cli handles uncaught Errors poorly

• Component: JavaScriptCore
• Status: NEW ---

[Mark Hahnenberg]

(1) Require a module (e.g. require('assert'))
(2) Call a function that that module exports.
(3) If the function throws an uncaught Error, we swallow it and do nothing.

We should instead catch the Error at the top level, print some info about where it came from, and exit with error code.