FTP: Redirect error to higher layer.

* Changes behavior of download function in ftp_utils.py. It was
  silencing the download error, now it is redirected to a higher
  layer.

Contrast_out: Change printed messages.
edpsciences_package: Astrophysics subject added

Signed-off-by: Georgios Papoutsakis <georgios.papoutsakis@cern.ch>
global: refextract indentifier added

* Adds the subfield 9995C9:refextract for
  references extracted with refextract.

Signed-off-by: Georgios Papoutsakis <georgios.papoutsakis@cern.ch>
Merge branch 'master' of github.com:inspirehep/harvesting-kit

Conflicts:
	harvestingkit/ftp_utils.py
Merge pull request #58 from Dziolas/master

FTP: Redirect error to higher layer.
global: Bibrecord dependecy removed.

Signed-off-by: Georgios Papoutsakis <georgios.papoutsakis@cern.ch>
edpsciences_package: attach fulltext fix

* Modifies _attach_fulltext function to handle url timeout errors
  and retries to open the url 10 times.

Signed-off-by: Georgios Papoutsakis <georgios.papoutsakis@cern.ch>
jats_package: empty affiliation fix

* Handles the case of empty affiliations.

Signed-off-by: Georgios Papoutsakis <georgios.papoutsakis@cern.ch>
global: refextract calls surrounded in try blocks

* Sometimes the refextract calls produce a RuntimeError
  maximum recursion depth this commit surrounds refextract
  calls with try blocks to avoid the task's termination untill
  the problem is fixed.

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