nexus file: link names not nexus compliant
Reported by @sole. The link names should correspond to ^(?!_+$)[A-Za-z0-9_](?:[A-Za-z0-9_.]*[A-Za-z0-9_])?$
Reported by @sole. The link names should correspond to ^(?!_+$)[A-Za-z0-9_](?:[A-Za-z0-9_.]*[A-Za-z0-9_])?$