elasticsearch dependency
first shot at ElasticSearch ParagraphDisambiguator
added prototypical scripts for ElasticSearch indexing

- Python script that transforms pignlproc output to ElasticSearch bulk index JSONs
-- this should probably become a Scala script in order to use all proven classes for creating URIs, resolving redirects etc.

- first shot at ElasticSearch mapping JSON
-- incomplete! analyzers etc. have to be specified correctly

- sketch of indexing script that goes from pignlproc output to an ElasticSearch disambiguation index
updates to indexing scripts

- "update" operations are required in order not to overwrite documents
- more shards, less replicas
- JSON encoding issues