CMS: link update in `cms-tools-ana.xml`

* Updates record links in `cms-tools-ana.xml`.  (closes #527) (PR #531)
LHCb: accelerator/experiment in `lhcb-tools.xml`

* Adds accelerator/experiment field in `lhcb-tools.xml`.
  (addresses #145) (PR #537)
LHCb: DOI in `cms-masterclass-files.xml`

* Adds DOIs for `cms-masterclass-files.xml` records.
  (PR #532)
CMS: DOI and other updates in `cms-csv-files.xml`

* Assigns DOI, adds link to parent dataset, adds 256 field.
  (PR #530)