docs: fix spelling in getting started with overlay

* Adds note about documentation for translations.  (PR #2595)

Reviewed-by: Jiri Kuncar <jiri.kuncar@cern.ch>
Signed-off-by: Johnny Mariéthoz <Johnny.Mariethoz@rero.ch>
elasticsearch: fix for signal receivers arguments

* Adds keyword arguments to signal receivers.  (PR #2594)

Acked-by: Jiri Kuncar <jiri.kuncar@cern.ch>
Signed-off-by: Johnny Mariéthoz <Johnny.Mariethoz@rero.ch>
sorter: multiple tag sorting fixes

* Fixes issue in sorting according to multiple MARC tags.

* Fixes issue with ordering of sorted records as well as handling of
  unsorted records.

* Fixes record slicing issue using 1-indexed value instead of
  0-indexed value.

* Adds generic method to decide whether to rank or sort records and
  changes facets to use this method.

* Adds two configuration variables to control default sort field and
  order.

Signed-off-by: Lars Holm Nielsen <lars.holm.nielsen@cern.ch>
communities: featured community UI problems fixup

* Fixes the `Curate` button link and the translated string
  for the empty collection.

Reviewed-by: Jiri Kuncar <jiri.kuncar@cern.ch>
Signed-off-by: Adrian Pawel Baran <adrian.pawel.baran@cern.ch>
alerts: PEP8/257 improvements in models

Signed-off-by: Jiri Kuncar <jiri.kuncar@cern.ch>
search: UserQuery relationship addition

Signed-off-by: Jiri Kuncar <jiri.kuncar@cern.ch>
authors: initial release

* Initial module structure.

* Introduces SQLAlchemy models for Publication, Author, Signature and
  Citation.

* Introduces claiming operations on signatures.

* Adds citation association table.

* Tests for models.

Signed-off-by: Artem Tsikiridis <artem.tsikiridis@cern.ch>
Co-authored-by: Gilles Louppe <gilles.louppe@cern.ch>
Co-authored-by: Mateusz Susik <mateusz.susik@cern.ch>
Co-authored-by: Evangelos Tzemis <evangelos.tzemis@cern.ch>
search: initial query parser usage
indexer: port of field tokenizer cache

Signed-off-by: Jiri Kuncar <jiri.kuncar@cern.ch>
wip
search: new match record API

Signed-off-by: Jiri Kuncar <jiri.kuncar@cern.ch>
search: port of logging and fulltext terms

Signed-off-by: Jiri Kuncar <jiri.kuncar@cern.ch>
search: fix for sorting and ranking