Detect e-mail address changes

[taniabogatsch]

Attention: Log in errors might occur after a change of your university e-mail address. In this case please contact the support.

Possible errors:

• Error message when attempting to log in.
• Your enrollments (active, expired) are associated with your old e-mail address and are no longer visible after logging in with your new e-mail address.

Error code:

caller: user.go:231
error: ERROR: duplicate key value violates unique constraint "a_users_matr_nr_key" (SQLSTATE 23505)
msg: failed to update or insert ldap user
user: &{ID:0 LastName:SomeLastName FirstName:SomeFirstName EMail:[email protected] Salutation:ms [...] MatrNr:{Int32:12345AlteMatrNr Valid:true} [...]} [...]}