Allow Basic Auth Accounts to be mapped by CSV file

[TheWitness]

Is your feature request related to a problem? Please describe.
When using basic authentication, cacti will currently look for an @ sign, and if it finds it, it will use the information before the @ sign as the login account. But some customers do not use that account as the local account name. Provide a setting, that if the customer provides a static CSV file, that Cacti will search that CSV file for the basic account to use for login.

Describe the solution you'd like
The CSV file would look like the following:
thewitness, ladams
ronytoman, troman
...

So, if the user thewitness@cacti.net logs in using Basic authentication, the account 'ladams' would be used for login.

[netniV]

Would it not be better to have external auth lonks as a table within Cacti so that we can properly link LDAP and Basic alike ?