* move parquet-extensions from contrib to core, adds new hadoop parquet parser that does not convert to avro first and supports flattenSpec and int96 columns, add support for flattenSpec for parquet-avro conversion parser, much test with a bunch of files lifted from spark-sql
* fix avro flattener to support nullable primitives for auto discovery and now only supports primitive arrays instead of all arrays
* remove leftover print
* convert micro timestamp to millis
* checkstyle
* add ignore for .parquet and .parq to rat exclude
* fix legit test failure from avro flattern behavior change
* fix rebase
* add exclusions to pom to cut down on redundant jars
* refactor tests, add support for unwrapping lists for parquet-avro, review comments
* more comment
* fix oops
* tweak parquet-avro list handling
* more docs
* fix style
* grr styles
* Rename io.druid to org.apache.druid.
* Fix META-INF files and remove some benchmark results.
* MonitorsConfig update for metrics package migration.
* Reorder some dimensions in inner queries for some reason.
* Fix protobuf tests.
* Update defaultHadoopCoordinates in documentation.
To match changes applied in #5382.
* Remove a parameter with defaults from example configuration file.
If it has reasonable defaults, then why would it be in an example config file?
Also, it is yet another place that has been forgotten to be updated and will be forgotten in the future.
Also, if someone is running different hadoop version, then there's much more work to be done than just changing this property, so why give users false hopes?
* Fix typo in documentation.
- Attempt to make things clearer in general
- Point out that HDFS deep storage and MR jobs don't use the same loading mechanism
- Recommend using mapreduce.job.classloader = true when possible
1) Remove maven client from downloading extensions at runtime.
2) Provide a way to load Druid extensions and hadoop dependencies through file system.
3) Refactor pull-deps so that it can download extensions into extension directories.
4) Add documents on how to use this new extension loading mechanism.
5) Change the way how Druid tarball is generated. Now all the extensions + hadoop-client 2.3.0
are packaged within the Druid tarball.