*: fix legacy imports

This change reorganizes imports and renames the legacy flask extensions.

util/useremails.py

@@ -1,18 +1,22 @@
-import logging
 import json
-import features
+import logging
 
-from flask.ext.mail import Message
+from flask_mail import Message
+
+import features
 
 from app import mail, app, get_app_url
 from util.jinjautil import get_template_env
 
+
 logger = logging.getLogger(__name__)
 template_env = get_template_env("emails")
 
+
 class CannotSendEmailException(Exception):
   pass
 
+
 class GmailAction(object):
   """ Represents an action that can be taken in Gmail in response to the email. """
   def __init__(self, metadata):