Improve documents searching

[mnowotka]

This involves several substasks:

• [x] Add full journal name (not only abbreviation) in the documents endpoint
• [ ] Once it's added reindex elastic search engine so it's reflected on the new web interface
• [x] Add journal, abbreviation, full name, document title and authors to solr index
• [x] Make sure solr index is case insensitive (unfortunately right now that's not the case)