Added generic service to receive a DataFeed and index for ElasticSearch
This library is needed for spatial ElasticSearch searches, but can be excluded otherwise; since it is LGPL licensed it is excluded from the build and war file by default (commented in gradle file), but here for easy use if desired
Added spacial4j and lucene-spatial jars; found that these are needed at runtime even for non-spatial queries, evidently because of the way Groovy handles method def caching