Parsing bad JSON should result in error Quark can handle

[itamarst]

Right now in Python, and maybe other languages, if you try to parse non-JSON string as JSON you get an exception. This means you can't handle this in Quark.

    json = _JSONObject.parse((contents).contents);
  File "/usr/lib/python2.7/site-packages/quark_runtime.py", line 234, in parse
    return cls._wrap(cls._backend.loads(value, object_pairs_hook=cls._dict))
  File "/usr/lib/python2.7/json/__init__.py", line 352, in loads
    return cls(encoding=encoding, **kw).decode(s)
  File "/usr/lib/python2.7/json/decoder.py", line 364, in decode
    obj, end = self.raw_decode(s, idx=_w(s, 0).end())
  File "/usr/lib/python2.7/json/decoder.py", line 382, in raw_decode
    raise ValueError("No JSON object could be decoded")
ValueError: No JSON object could be decoded