1. Document the global option (elasticsearch.dynamic_mapping) in elasticsearch-integration.asciidoc
2. Document the custom field bridge option (org.hibernate.search.elasticsearch.bridge.spi.Elasticsearch)
3. There is a warning in the documentation that states "Creating sub-fields in custom field bridges is not supported." It is probably supported now that we can give fields the OBJECT type explicitly; maybe we should replace the warning with an explanation of how to create sub-fields in custom field bridges.