[necessary] Add all needed CRUD

[besteady]

• Read all papers
• Read one paper by id
• Read papers by title
• Read papers by abstract
• Read papers by tags
• Read papers by authors
• Read papers by venue.raw
• Create a paper
• Update a paper by id
• Delete a paper by id

[besteady]

@Volodimirich probably we need discuss what else we should add

[Volodimirich]

Perhaps we should run a cascade deletion experiment. Get paper by id -> Get id's of all paper in citation block -> Delete all selected papers. In this complex expieriment we check 'Read', 'Update'(partly), 'Delete' paradigms.