move to 0.20.3 snap
Move to 0.20.3-SNAPSHOT
fix thread pool stats largest
add plugin configuration to make m2e ignore maven dependency plugin configuration that it cannot handle
upgrade to netty 3.6.1
Fixed document already exists error when concurrently sending update request with upsert using the same id.

Closes #2530
Fixed issue where parent & child queries can fail if a segment doesn't have documents with the targeted type or associated parent type

Closes #2537
Disallow unknown custom indexing parameters

Fixes #2354
Make script cache configurable and bounded

Fixes #2539
upgrade to netty 3.6.2
Added trace log statement, to catch stacktraces
Added filter support in the `has_child` and `has_parent` filters.

Example:
```
curl -XPOST 'localhost:9200/_search' -d '{
  "query": {
    "filtered_query": {
      "query": {
        "match": {
          "title": "distributed systems"
        }
      },
      "filter": {
        "has_child": {
          "type": "tag",
          "filter": {
            "term": {
              "name": "book"
            }
          }
        }
      }
    }
  }
}'
```

Closes #2588

Conflicts:
	src/main/java/org/elasticsearch/index/query/HasChildFilterParser.java
	src/main/java/org/elasticsearch/index/query/HasParentFilterParser.java
eagerly reroute when a node leaves the cluster
Primary shard failure with initializing replica shards can cause the replica shard to cause allocation failures
fixes #2592
release 0.20.3
move to 0.20.4 snap
Indexes created from index request might not replica initial doc to replica
fixes #2594
Support MultiPhrasePrefixQuery and MultiPhraseQuery in highlighters

Closes #2596
release 0.20.4
move to 0.20.5 snap