Systems: Calling globus auth endpoints for a non-globus system type should not attempt the operation

[scblack321]

It appears that when a request is made for one of the two globus auth endpoints and the system is not of type GLOBUS the Systems service still attempts to perform the operation. This will probably give a misleading error and is almost certainly not intended.

Check for this case and return a more reasonable error, HTTP code 400 = bad request.