Add Magellan Clay and spectrograph to instrument list

[dekishalay]

Could you please add the following telescope and instrument. Thanks!
{'name': 'Magellan Clay',
'nickname': 'Magellan_Clay',
'diameter': 6.5,
'robotic': False,
'lat': -29.018,
'lon': -70.691,
'elevation': 2380,
'fixed_location': True
}

and the imaging spectrograph on Magellan Clay
{'name': 'LDSS-3',
'type': 'imaging spectrograph',
'band': 'optical',
'telescope_id': ,
}

[mcoughlin]

Done.