Fixed `has_parent` query and filter returning no results with multi level child docs.
Added a benchmark for parent/child queries while indexing at the same time.
More test cleanups
report details if shard response has failed shards
Correct offsets in FVH also if stored field is used for highlighting

The SimpleFragemntsBuilder did not correct offsets if the used
analysis chais could produce broken offsets that could lead to
StringArrayIndexOutOfBounds Exceptions

Closes #3140
Fallback to extract terms if MultiPhraseQuery is large

Currently if MPQ is very large highlighing can take down a node
or cause high CPU / RAM consumption. If the query grows > 16 terms
we just extract the terms and do term by term highlighting.

Closes  #3142 #3128
Stabelize more tests

Wait for relocation before checking statistics or run refresh / optimze.
ChildrenQuery and ParentQuery now take into account documents that have been marked.

Closes #3144
Fixed minor issue in ASCT#indexExists(...)
Added shortcuts for several common commands

added simple way to add more complex mappings as well as shortcuts for flush
and status etc. all checking if requests return failed shards
Simplify TestCluster

TestCluster now doesn't use any reference counting anymore and
testcluster names are based on creation time to prevent confilcts if
builds hang.
Fixed the `GeoPointFieldMapper` to parse `geohashes` correctly.

Closes #3073
Add more verbose matchers / asserts to tests
Ensure all shards return compareable scores for rescore tests
Cleaning up some tests by using assertHitCount assertion
Cleanup String to UTF-8 conversion

Currently we have many different places that convert String to UTF-8
bytes and back. We shouldn't maintain more code than necessary to
do this conversion and rather use Lucene's support for it.
Thread pool: rename `capacity` to `queue_size`
fixes #3161
Fix addMapping() in AbstractSharedClusterTest for more than one field
no need for the test
fix shared cluster to delete templates as well per test run