Merge branch 'stable-3.2' into stable-3.3

* stable-3.2:
  Update git submodules
  Update git submodules
  Update git submodules
  Compact the REST-API output JSON unconditionally
  Elasticsearch: Discontinue EOL versions 7.0 and 7.1 support
  Elasticsearch: Discontinue EOL version 6.8 thus whole V6 support
  Update git submodules
  Avoid logging "length=0" exception

Change-Id: I4cae34338b02fa7fa8c016e0158be261a77b87c6
tree: fa6a667e0ee7668105eacc037f305a480264799b
  1. java/
  2. javatests/