Server crashes if data comes in as a dictionary instead of floating point value.

Should send back a failure to the client.
Traceback (most recent call last):

  File "/usr/local/lib/python2.7/dist-packages/django/core/handlers/base.py", line 114, in get_response
    response = wrapped_callback(request, *callback_args, **callback_kwargs)

  File "/usr/local/lib/python2.7/dist-packages/django/views/decorators/csrf.py", line 57, in wrapped_view
    return view_func(*args, **kwargs)

  File "/home/sfr/chain-api/chain/core/api.py", line 748, in create_view
    return cls.create_single(data, request)

  File "/home/sfr/chain-api/chain/core/api.py", line 755, in create_single
    new_resource.save()

  File "/home/sfr/chain-api/chain/core/api.py", line 544, in save
    self.deserialize()

  File "/home/sfr/chain-api/chain/core/api.py", line 495, in deserialize
    self._data[field_name])

  File "/home/sfr/chain-api/chain/core/api.py", line 476, in sanitize_field_value
    return field.to_python(value)

  File "/usr/local/lib/python2.7/dist-packages/django/db/models/fields/__init__.py", line 1055, in to_python
    params={'value': value},

ValidationError: [u"'{u'power_good': True, u'charging': False}' value must be a float."]

<WSGIRequest
path:/scalar_data/create,
GET:<QueryDict: {u'sensor_id': [u'2763']}>,
POST:<QueryDict: {}>,
COOKIES:{},
META:{'CONTENT_LENGTH': '99',
 u'CSRF_COOKIE': u'eaEEB0wRmMcpPo8dTVZvMKObdFPvyhZn',
 'HTTP_ACCEPT': '*/*',
 'HTTP_ACCEPT_ENCODING': 'gzip, deflate',
 'HTTP_AUTHORIZATION': 'Basic Y2hhaW5jb2xsZWN0b3JzOlY4VGlPRTZ5VndwaklpbTEzeWJoakE5Tw==',
 'HTTP_CONNECTION': 'close',
 'HTTP_HOST': 'chain-api.media.mit.edu',
 'HTTP_USER_AGENT': 'python-requests/2.3.0 CPython/2.7.3 Linux/3.11.0-26-generic',
 'HTTP_X_FORWARDED_FOR': '18.85.58.252',
 'PATH_INFO': u'/scalar_data/create',
 'QUERY_STRING': 'sensor_id=2763',
 'RAW_URI': '/scalar_data/create?sensor_id=2763',
 'REMOTE_ADDR': '18.85.58.252',
 'REMOTE_PORT': '80',
 'REQUEST_METHOD': 'POST',
 'SCRIPT_NAME': u'',
 'SERVER_NAME': 'chain-api.media.mit.edu',
 'SERVER_PORT': '80',
 'SERVER_PROTOCOL': 'HTTP/1.0',
 'SERVER_SOFTWARE': 'gunicorn/18.0',
 'gunicorn.socket': <socket._socketobject object at 0x294a520>,
 'wsgi.errors': <open file '<stderr>', mode 'w' at 0x7fd4a1bc9270>,
 'wsgi.file_wrapper': <class gunicorn.http.wsgi.FileWrapper at 0x1842668>,
 'wsgi.input': <gunicorn.http.body.Body object at 0x2afd950>,
 'wsgi.multiprocess': True,
 'wsgi.multithread': False,
 'wsgi.run_once': False,
 'wsgi.url_scheme': 'http',
 'wsgi.version': (1, 0)}>
ResEnv / chain-api

Server crashes if data comes in as a dictionary instead of floating point value. #61
