Fix error handling of LDAP-Login, closes #223

db.py

@@ -126,7 +126,7 @@ if 'LDAP_HOST' in config:
 			conn.unbind()
 			return user, groups
 		except ldap3.core.exceptions.LDAPBindError:
-			pass
+			return None, []
 
 	def ldapget(user):
 		user = LDAP_USERRE.sub(r'', user.lower())