repl: show exception for out-of-range unicode escape sequence

[bnoordhuis]

> '\u{10fffe}'
'???'
> '\u{10ffff}`
'???'
> '\u{110000}'
... 

The REPL hangs waiting for completion because of the SyntaxError: Unexpected token ILLEGAL exception.

[targos]

related: #3611

[thefourtheye]

REPL treats all these errors as Recoverable errors and it doesn't fail immediately.

[princejwesley]

@bnoordhuis see #5189

[princejwesley]

@bnoordhuis @thefourtheye @targos Working!

~ 🙈 ₹ node
> '\u{110000}'
SyntaxError: Unexpected token ILLEGAL
    at Object.exports.createScript (vm.js:47:10)
    at REPLServer.defaultEval (repl.js:255:25)
    at bound (domain.js:280:14)
    at REPLServer.runBound [as eval] (domain.js:293:12)
    at REPLServer.<anonymous> (repl.js:489:10)
    at emitOne (events.js:101:20)
    at REPLServer.emit (events.js:188:7)
    at REPLServer.Interface._onLine (readline.js:232:10)
    at REPLServer.Interface._line (readline.js:574:8)
    at REPLServer.Interface._ttyWrite (readline.js:851:14)
> process.version
'v6.3.0'

[targos]

Nice!