Bibcheck: Adds a plugin to correct author names

* Corrects the authors using a knwoledge base file with observed errors.

Signed-off-by: Georgios Papoutsakis <georgios.papoutsakis@cern.ch>
BibCheck: adds a new plugin and unit tests

* Adds journal_names plugin.

* Adds unit tests for the new plugin and
  atlas_authors plugin.

* Fixes pep8 issues on atlas_authors.

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