OAIHarvest: Integrate new workflows

• Refactor oai_harvest_daemon to use new workflows module for post process.

• Several PEP8 fixes.

Bibworkflow: MarcXML processing workflow

• Sub workflow exception improvement which allow to centralize all the exceptions of children workflow and to get the full stacktrace of each

• Convert_record_to_bibfield task for workflow which convert any marcxml file to a dictionnary thanks to bibfield, the goal is to avoid the old file system based inter function communication protocol

• Post_process after celery reception of an WorkflowObject to reattach to the new DB instance all the DB object which couled be not referenced

• Add security of type cohesion into the WorkflowObject Transporter, it is a hot fix in wait of the database modification which allow to tranform potential string representation of dictionnary into dictionnary.

• New workflow tasks, all compatibles with bibifield dictionnary representation fulltext_download with bibfield support, plot_extract with bibfield support, ref_extraction witht bibfield support, author_list witht bibfield support

OAIHarvest: Various import fixes and PEP8

Conflicts:
invenio/legacy/oaiharvest/daemon.py