Crashes adding a policy version

[Tony Locke]

Traceback (most recent call last):
  File "/python27_runtime/python27_lib/versions/1/google/appengine/runtime/wsgi.py", line 223, in Handle
    result = handler(dict(self._environ), self._StartResponse)
  File "/python27_runtime/python27_lib/versions/third_party/webapp2-2.3/webapp2.py", line 1519, in __call__
    response = self._internal_error(e)
  File "/python27_runtime/python27_lib/versions/third_party/webapp2-2.3/webapp2.py", line 1511, in __call__
    rv = self.handle_exception(request, response, e)
  File "/python27_runtime/python27_lib/versions/third_party/webapp2-2.3/webapp2.py", line 1505, in __call__
    rv = self.router.dispatch(request, response)
  File "/python27_runtime/python27_lib/versions/third_party/webapp2-2.3/webapp2.py", line 1253, in default_dispatcher
    return route.handler_adapter(request, response)
  File "/python27_runtime/python27_lib/versions/third_party/webapp2-2.3/webapp2.py", line 1077, in __call__
    return handler.dispatch()
  File "/base/data/home/apps/s~polifesto-hrd/1.367162614152786092/polifesto.py", line 44, in dispatch
    webapp2.RequestHandler.dispatch(self)
  File "/python27_runtime/python27_lib/versions/third_party/webapp2-2.3/webapp2.py", line 547, in dispatch
    return self.handle_exception(e, self.app.debug)
  File "/python27_runtime/python27_lib/versions/third_party/webapp2-2.3/webapp2.py", line 545, in dispatch
    return method(*args, **kwargs)
  File "/base/data/home/apps/s~polifesto-hrd/1.367162614152786092/polifesto.py", line 528, in post
    self.return_bad_request(self.make_fields(policy, str(e)))
TypeError: make_fields() takes exactly 2 arguments (3 given)

[Tony Locke]

Fixed and added test.