Improved bst_scoap3_importer

* Better message reporting and sleeping points.

* Match also against DOIs
BibFormat: fix unreferenced variable
BibFormat: refactoring of bfe_INSPIRE_Conferences_other_conf
BibFormat: bfe_INSPIRE_links and pdf/a

* Whitelist also PDF/A files so that they are displayed
  in the fulltext area.
BibFormat: stricter input data in ref correction form

* Makes sure record_id is an integer in the references correction form.
BibFormat: allow PoS fulltext links

* Modifies bfe_INSPIRE_links format element to also allow PDFs
  with the "PoS" doctype to be rendered.

Signed-off-by: Jan Aage Lavik <jan.age.lavik@cern.ch>
BibExport: disable fulltext export in sitemap
BibRank: citation_loss_per_record_limit in citation.cfg
Bibharvest: new filter for PoS

* Downloads fulltexts and adds the proper FFT datafield

* creates 3 files:
  append.xml for already existing records
  insert.xml for non existing records
  not_found.xml when fulltext harvest fails

* Adds beatifulsoup4 requirement

* Amends bibharvest/Makefile to setup the new filter

Signed-off-by: Georgios Papoutsakis <georgios.papoutsakis@cern.ch>