This commit forbids the changing of thread pool types for any thread
pool. The motivation here is that these are expert settings with
little practical advantage.
Closes#14294, relates #2509, relates #2858, relates #5152
IndexQueryParserService is only a factory for QueryShardContext instances
which are not even bound to a shard. The service only forwards dependencies and even
references node level service directly which makes dependency seperation on shard,
index and node level hard. This commit removes the service entirely, folds the creation
of QueryShardContext into IndexShard which is it's logical place and detaches the
ClusterService needed for index name matching during query parsing with a simple predicate
interface on IndexSettings.
The test jar was previously built in maven by copying class files. With
gradle we now have a proper test framework artifact. This change moves
the classes used by the test framework into the test-framework module.
See #13930
Simon Willnauer
Jason Tedor
Ryan Ernst