Add postgres fulltext search capability

Postgres has good support for full text search that can be used for e.g. product description search. Fulltext search is different to using LIKE %keyword% because humans tend to search differently. Usage of elasticsearch/lucene is overkill so postgres search might be the perfect fit.
Example: https://www.crunchydata.com/blog/postgres-full-text-search-a-search-engine-in-a-database