epdsciences_package: adds new module

* to convert the metadata from edpsciences to marc xml.

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

* Fixes author name capitalization.

* Removes unused functions.

Signed-off-by: Georgios Papoutsakis <georgios.papoutsakis@cern.ch>
Tests: Adds unit tests for PoS APS and Edp Sciences packages.

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