Cannot get a sessionToken using basic auth

[cadegenn]

Problem Configuring glpi_app_grafan with basic auth does not work.

There is in fact 2 problems:

1. User Token field is mandatory in the grafana's GLPI datasource configuration GUI. IMHO it is a mistake as the GLPI's API allow other kind of authentications.
2. The GUI of GLPI datasource configuration allow user to configure basic authentication, but it is ignored.

I found seral places where code calls this.url + "/initSession" and each time it build query with user_token header field.

It should test wich fields it needs and allow use of Autorization: basic with a base64 hash of user: passwd fields as stated in the GLPI's APIREST documentation.

In our environment, using App-Token and User-Token does not work because we authenticate GLPI users with CAS. Maybe it is a bug in GLPI implementation, I don't know.

We use plugin glpi_app_grafana v1.3.0

Thank you