Major updates on indexing and search for AGRIF

1. agro-domain: models for Agrif are created (along with Akif)
2. agro-indexer: changed to support both formats (with generics and no code duplication)
3. agro-indexer: logback conf changed to log to stdout as well as files
4. agro-search: changed to support both formats (again generic based on both service and controller layer)
5. agro-search: documentation cleanup and update

* we miss detailed mapping on agrif elasticsearch index creation script to complete AGRIF support. And of course testing...