title: djongo, unable to connect to remote db on cloud.mongodb.com
body: <p>i think below setting will work for the djongo to connect to the remote mongodb on mongodb.com but, the error message shows its still trying to connect to the localhost</p>
  
  <pre><code>DATABASES = {
      'default': {
          'ENGINE': 'djongo',
          'HOST': 'mongodb+srv://&lt;username&gt;:&lt;password&gt;@cluster-name/&lt;dbname&gt;?retryWrites=true&amp;w=majority',
  }
  </code></pre>
  
  <p>below is the error traceback</p>
  
  <pre><code>Traceback (most recent call last):
    File "/usr/lib/python3.6/threading.py", line 916, in _bootstrap_inner
      self.run()
    File "/usr/lib/python3.6/threading.py", line 864, in run
      self._target(*self._args, **self._kwargs)
    File "venv/lib/python3.6/site-packages/django/utils/autoreload.py", line 54, in wrapper
      fn(*args, **kwargs)
    File "venv/lib/python3.6/site-packages/django/core/management/commands/runserver.py", line 120, in inner_run
      self.check_migrations()
    File "venv/lib/python3.6/site-packages/django/core/management/base.py", line 453, in check_migrations
      executor = MigrationExecutor(connections[DEFAULT_DB_ALIAS])
    File "venv/lib/python3.6/site-packages/django/db/migrations/executor.py", line 18, in __init__
      self.loader = MigrationLoader(self.connection)
    File "venv/lib/python3.6/site-packages/django/db/migrations/loader.py", line 49, in __init__
      self.build_graph()
    File "venv/lib/python3.6/site-packages/django/db/migrations/loader.py", line 212, in build_graph
      self.applied_migrations = recorder.applied_migrations()
    File "venv/lib/python3.6/site-packages/django/db/migrations/recorder.py", line 73, in applied_migrations
      if self.has_table():
    File "venv/lib/python3.6/site-packages/django/db/migrations/recorder.py", line 56, in has_table
      return self.Migration._meta.db_table in self.connection.introspection.table_names(self.connection.cursor())
    File "venv/lib/python3.6/site-packages/django/db/backends/base/introspection.py", line 48, in table_names
      return get_names(cursor)
    File "venv/lib/python3.6/site-packages/django/db/backends/base/introspection.py", line 43, in get_names
      return sorted(ti.name for ti in self.get_table_list(cursor)
    File "venv/lib/python3.6/site-packages/djongo/introspection.py", line 47, in get_table_list
      for c in cursor.db_conn.list_collection_names()
    File "venv/lib/python3.6/site-packages/pymongo/database.py", line 856, in list_collection_names
      for result in self.list_collections(session=session, **kwargs)]
    File "venv/lib/python3.6/site-packages/pymongo/database.py", line 819, in list_collections
      _cmd, read_pref, session)
    File "venv/lib/python3.6/site-packages/pymongo/mongo_client.py", line 1454, in _retryable_read
      read_pref, session, address=address)
    File "venv/lib/python3.6/site-packages/pymongo/mongo_client.py", line 1253, in _select_server
      server = topology.select_server(server_selector)
    File "venv/lib/python3.6/site-packages/pymongo/topology.py", line 235, in select_server
      address))
    File "venv/lib/python3.6/site-packages/pymongo/topology.py", line 193, in select_servers
      selector, server_timeout, address)
    File "venv/lib/python3.6/site-packages/pymongo/topology.py", line 209, in _select_servers_loop
      self._error_message(selector))
  pymongo.errors.ServerSelectionTimeoutError: localhost:27017: [Errno 111] Connection refused
  </code></pre>