Finalize mail settings admin UI and Mailrise compatibility

app/utils/token.py

@@ -0,0 +1,19 @@
+import os
+from itsdangerous import URLSafeTimedSerializer
+from flask import current_app
+
+def get_serializer():
+    secret = os.environ.get('RESET_TOKEN_SECRET') or current_app.config.get('SECRET_KEY')
+    return URLSafeTimedSerializer(secret)
+
+def generate_reset_token(email):
+    s = get_serializer()
+    return s.dumps(email, salt='password-reset')
+
+def verify_reset_token(token, max_age=3600):
+    s = get_serializer()
+    try:
+        email = s.loads(token, salt='password-reset', max_age=max_age)
+        return email
+    except Exception:
+        return None