htmlutils: render MathML by MathJax

* Adds config variable CFG_MATHJAX_RENDERS_MATHML to enable or disable
  rendering of MathML via MathJax.
* Changes function responsible for loading MathJax to load
  different configuration version according to CFG_MATHJAX_RENDERS_MATHML.
* Amends part numbering in invenio.conf.

Signed-off-by: Wojciech Ziolek <wojciech.ziolek@cern.ch>
Reviewed-by: Samuele Kaplun <samuele.kaplun@cern.ch>
crossrefutils: new Fundref-based APIs

* Introduces new query_fundref_api() and get_all_modified_dois()
  functions, namely needed by the SCOAP3 project, allowing to
  query the Fundref-based Crossref APIs to discover when
  new DOIs are registered by given publishers. This indirectly
  allows to approximately know when they are first created,
  an information that is not available through the regular
  Crossref APIs.

Signed-off-by: Samuele Kaplun <samuele.kaplun@cern.ch>
BibFormat: affiliation improvements

* In case 100__v or 700__v are available, but not
  100__u or 700__u fallback on $v.

* Introduces new multiple_affiliations flag in
  bfe_authors.py in order to optionally display
  multiple affiliations in case these are available.

Signed-off-by: Samuele Kaplun <samuele.kaplun@cern.ch>
BibFormat: new bfe_arxiv_link

* Introduces new bfe_arxiv_link format element
  that automatically creates a link to arXiv.

Signed-off-by: Samuele Kaplun <samuele.kaplun@cern.ch>
general: new CFG_SCOAP3_SITE flag

* Introduces new CFG_SCOAP3_SITE flag to introduce
  SCOAP3 specific modifications in core modules.

* If CFG_SCOAP3_SITE=1 renames collections accordingly
  to journals or publishers.

Signed-off-by: Samuele Kaplun <samuele.kaplun@cern.ch>
BibDocFile: get_file() exact_docformat support

* Introduces new argument exact_docformat to
  BibDoc.get_file() method, allowing to actually
  retrieving a given file matching an exact
  docformat (including the subformat).

Signed-off-by: Samuele Kaplun <samuele.kaplun@cern.ch>
BibDocFile: textification with OCR fix

* Textification with OCR is based on a pattern matching
  against the the docname of a BibDoc. This has become a
  property between a record and a BibDoc. The code
  is here updated, thus allowing again textification
  to work.
  (fixes #1676)

Signed-off-by: Samuele Kaplun <samuele.kaplun@cern.ch>
BibFormat: file rights fix

* Fixes UNIX file rights in the GIT repository.

Signed-off-by: Samuele Kaplun <samuele.kaplun@cern.ch>