When trying to open connection to Atlas cluster, pymongo failed with ServerSelectionTimeoutError due to wrong fqdn record. This is because we send the full fqdn with the dot at the end of the url.
See full stack trace:
```File "/opt/fundbox/venvs/backend/fetching/local/lib/python2.7/site-packages/mongoengine/queryset/manager.py", line 37, in _get_
queryset = queryset_class(owner, owner._get_collection())
File "/opt/fundbox/venvs/backend/fetching/local/lib/python2.7/site-packages/mongoengine/document.py", line 176, in _get_collection
db = cls._get_db()
File "/opt/fundbox/venvs/backend/fetching/local/lib/python2.7/site-packages/mongoengine/document.py", line 169, in _get_db
return get_db(cls._meta.get('db_alias', DEFAULT_CONNECTION_NAME))
File "/opt/fundbox/venvs/backend/fetching/local/lib/python2.7/site-packages/mongoengine/connection.py", line 234, in get_db
db.authenticate(conn_settings['username'], conn_settings['password'], **auth_kwargs)
File "/opt/fundbox/venvs/backend/fetching/local/lib/python2.7/site-packages/pymongo/database.py", line 1075, in authenticate
connect=True)
File "/opt/fundbox/venvs/backend/fetching/local/lib/python2.7/site-packages/pymongo/mongo_client.py", line 542, in _cache_credentials
writable_preferred_server_selector)
File "/opt/fundbox/venvs/backend/fetching/local/lib/python2.7/site-packages/pymongo/topology.py", line 214, in select_server
address))
File "/opt/fundbox/venvs/backend/fetching/local/lib/python2.7/site-packages/pymongo/topology.py", line 189, in select_servers
self._error_message(selector))
ServerSelectionTimeoutError: hostname 'cluster0-shard-00-01-xxxxx.mongodb.net.' doesn't match either of '.mongodb.net', 'mongodb.net',hostname 'cluster0-shard-00-00-xxxxx.mongodb.net.' doesn't match either of '.mongodb.net', 'mongodb.net',hostname 'cluster0-shard-00-02-xxxxx.mongodb.net.' doesn't match either of '*.mongodb.net', 'mongodb.net'
[9910:140625621952256] ```

It is not an issue with Atlas as I can open a valide connection from my environment directly to such URI:
:~$ openssl s_client -showcerts -connect cluster0-shard-00-02-xxxxx.mongodb.net.:27017
CONNECTED(00000003)
depth=2 C = US, O = DigiCert Inc, OU = www.digicert.com, CN = DigiCert Global Root CA
verify return:1
depth=1 C = US, O = DigiCert Inc, CN = DigiCert SHA2 Secure Server CA
verify return:1
depth=0 C = US, ST = New York, L = New York, O = "MongoDB, Inc.", CN = *.mongodb.net
verify return:1