[bug 873635] Fix index_chunk and esreindex output

* fix index_chunk to break up the documents to bulk index in small
  chunks
* fix recreate_index to wait until a shard is yellow before continuing
* fix esreindex command output so the deltas and ETAs are more correct
Drop chunk size down to 10000
Set CELERYD_TASK_SOFT_TIME_LIMIT to 10 minutes

This will reduce indexing failures.