Provide additional parameters for login

[snowch]

{
  "name": "admin",
  "password": "admin",
  "domain": "string",
  "saml_response": "string",
  "tenant_key": "string",
  "tenant": "/api/v1/tenant/2",
  "tenant_name": "Demo Tenant"
}

[snowch]

{
  "password": "string",
  "tenant": "/api/v1/tenant/2",
  "tenant_name": "Demo Tenant",
  "site_admin_view": true
}

There is also a site_admin_view parameter for /session

[snowch]

Tenant parameter implemented with dc1a111