Use role claims from IdP

[nafai]

Hi,

It would be convenient to be able to pass a list of roles from the IdP. This would remove the need to assign them within MeshCentral.

I'm using the Azure auth strategy, but this feature request would apply for other strategies as well, such as SAML. As far as I can tell, this isn't currently supported, but please feel free to yell at me if I'm wrong. Cheers!