[Network] Feature Request: Allow configuration of authentication methods

[eliasboegel]

Currently, as far as I can tell, network authentication is essentially inputting the network password. However, that is not enough for some corporate networks that require setting different authentication methods or require configuartion with a user name, domain, etc.

In combination with #483, this means that such networks can't even be set up in a functional way, as even if set up in a manual way or through another NM config tool, the connection configuration is reset or changed. One example of those networks is Eduroam, so I would rank the severity of that problem medium-high compared to other network applet issues as long as #483 is a problem.