#304 Deleting "name" field results in fatal error with no warning

[jcrawford]

When an admin removes the field "Name" from an object, it results in a fatal error. This is because the Name field is required, as it is used for sorting devices when they are listed. However, the system did not warn users of this. Thus removing the name field results in a blank screen (of death) with no warning.

Suggest checking delete requests in the device editor against a list of required fields, and informing the user if the field cannot be deleted.