Support handling 404s when a resource has been deleted

[bstoutenburgh]

We've had several instances of a human user deleting views that are managed by terraform, which the provider does not handle well.

Error: Cannot read the remote view resource

  with module.logdna-views-prod.logdna_view.errors_in_satellite,
  on ../../modules/logdna_prod/main.tf line 822, in resource "logdna_view" "errors_in_satellite":
 822: resource "logdna_view" "errors_in_satellite" {

GET https://REDACTED_HOSTNAME/v1/config/view/REDACTED_ID, status 404 NOT OK! {"error":"Resource Not Found","code":"NotFound","status":"error"}

Typically providers see this as needing to recreate the resource.

[gjanco]

Will be tracked by #53

[gjanco]

Duplicate of #53