Merge pull request #14 from GiorgosPa/elsevier

elsevier_package: encodes unicode objects to str
elsevier_package: change FFT argument

* Changes the FFT argument to $o to uppercase HIDDEN.

Signed-off-by: Jan Aage Lavik <jan.age.lavik@cern.ch>
elsevier_package: various fixes for CONSYN

* Journal volume letter is now prepended on field 999C5s

* Fixes mathml handling of refextract

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