Implement model search engine for content/tag selection

[shah]

Check out liqe Lucene-like parser and search engine for free-text searching of structured JSON. This would allow us to search resources' models, frontmatter, and other content for tags, taxonomy terms, etc. We could allow searching to be done at build time on the server or dynamically at runtime.

Another useful integration might be AlaSQL JavaScript SQL database for browser and Node.js which would allow searching for all RF-based resources' models as SQL.

Check out #43 for a related idea.