Dead links in `target`

[cverluise]

Issue

There are dead links in the target field. (e.g Http://Edrm.Net/002/Wp-Content/Uploads/2009/09/Edrm-Legaltech.Pdf )

How to reproduce the behaviour

SELECT
  npl_publn_id,
  target
FROM
  `npl-parsing.patcit.beta`
WHERE
  npl_publn_id=260140

npl_publn_id	target
260140	Http://Edrm.Net/002/Wp-Content/Uploads/2009/09/Edrm-Legaltech.Pdf

Request

Might be nice to flag (remove?) dead links