Infer concepts for project relations imported from InformationSpace

[marekhorst]

Currently fet-fp7 and fet-h2020 concepts are inferred only for publication to project relations inferred by project reference extraction algorithm.

Since there is pretty large amount of relations already existing in InformationSpace (120789, e.g. coming from claims) we could include them when inferring concepts.

Such relations are already imported by IIS for different purposes so the only required change would be to:

• introduce module transforming eu.dnetlib.iis.importer.schemas.DocumentToProject imported records into eu.dnetlib.iis.referenceextraction.project.schemas.DocumentToProject records compatible with concepts inference module input requirements
• union two DocumentToProject sources: coming from import and inference
• update concepts inference input

[marekhorst]

Associated redmine ticket: #2561.