1. Upgrade elasticsearch dependency in src/plugin/indexer-elastic2/ivy.xml

2. Upgrade the Elasticsearch specific dependencies in src/plugin/indexer-elastic2/plugin.xml
   To get the list of dependencies and their versions execute:
   $ ant -f ./build-ivy.xml
   $ ls lib | sed 's/^/      <library name="/g' | sed 's/$/"\/>/g'
