Search engine

[oknozor]

Needed

Gill needs a search engine to provides the following UI features:

• search users
• search repositories
• search ticket, comment pull requests

Planned

Later we might want to implement code search but this is not a priority for v1.
That said choosing a search engine that would allow implementing code search (indexing code tags, references etc)
would avoid future breaking changes.

Contenders

• meilisearch
• sonic
• bayard