Improve automatic emails with temporary urls

This MR targets the improvement for automatic emails concerning validation of new users by supervisors/re-validation of users.

Fixes #542 (closed)

Fixes #550 (closed)

beat/web/accounts/views.py

@@ -56,10 +56,7 @@ from ..common.responses import BadRequestResponse, ForbiddenResponse
 from datetime import datetime, timedelta
 
 import datetime
-try:
-  from urlparse import urlparse
-except ImportError:
-  from urllib.parse import urlparse
+from urllib.parse import urlparse
 
 
 @login_required