Use zookeeper-api module in Apache Helix and remove IOItec import

[narendly]

Use this PR for reference for adopting future iterations of Apache Helix releases.
See https://github.com/apache/helix/wiki/New-Modules-for-Apache-Helix for details.

Changelist:

1. Remove IOItec import
2. Import newly created zookeeper-api module in Apache Helix
3. Build

NOTE: this PR excludes modules for Pinot Client and Kafka-related modules. Since Kafka depends on IOItec, I've decided to leave these two modules out.
NOTE: The Helix version used is a local snapshot. The official release is still pending. As such, no immediate action is required.

$ mvn clean install -Pbin-dist

[INFO] Pinot .............................................. SUCCESS [ 6.449 s]
[INFO] Pinot Service Provider Interface ................... SUCCESS [ 6.990 s]
[INFO] Pinot Common ....................................... SUCCESS [ 30.705 s]
[INFO] Pinot Plugins ...................................... SUCCESS [ 0.949 s]
[INFO] Pinot Input Format ................................. SUCCESS [ 0.322 s]
[INFO] Pinot Avro ......................................... SUCCESS [ 6.946 s]
[INFO] Pinot Csv .......................................... SUCCESS [ 5.948 s]
[INFO] Pinot JSON ......................................... SUCCESS [ 5.444 s]
[INFO] Pinot Core ......................................... SUCCESS [12:22 min]
[INFO] Pinot Server ....................................... SUCCESS [ 29.237 s]
[INFO] Pinot Controller ................................... SUCCESS [04:56 min]
[INFO] Pinot Broker ....................................... SUCCESS [01:29 min]
[INFO] Pinot Clients ...................................... SUCCESS [ 0.098 s]
[INFO] Pinot Java Client .................................. SUCCESS [ 2.685 s]
[INFO] Pinot Minion ....................................... SUCCESS [ 4.115 s]
[INFO] Pinot ORC .......................................... SUCCESS [ 9.134 s]
[INFO] Pinot Parquet ...................................... SUCCESS [ 11.487 s]
[INFO] Pinot Thrift ....................................... SUCCESS [ 2.642 s]
[INFO] Pluggable Pinot file system ........................ SUCCESS [ 0.137 s]
[INFO] Pinot Azure Data Lake Storage ...................... SUCCESS [ 2.771 s]
[INFO] Pinot Hadoop Filesystem ............................ SUCCESS [ 0.386 s]
[INFO] Pinot Google Cloud Storage ......................... SUCCESS [ 3.755 s]
[INFO] Pinot Batch Ingestion .............................. SUCCESS [ 0.875 s]
[INFO] Pinot Batch Ingestion Common ....................... SUCCESS [ 0.296 s]
[INFO] Pinot Batch Ingestion for Spark .................... SUCCESS [ 4.883 s]
[INFO] Pinot Batch Ingestion for Hadoop ................... SUCCESS [ 2.124 s]
[INFO] Pinot Batch Ingestion Standalone ................... SUCCESS [ 0.301 s]
[INFO] Pinot Batch Ingestion .............................. SUCCESS [ 0.562 s]
[INFO] Pinot Ingestion Common ............................. SUCCESS [ 0.869 s]
[INFO] Pinot Stream Ingestion ............................. SUCCESS [ 0.118 s]
[INFO] Pinot Kafka Base ................................... SUCCESS [ 3.238 s]
[INFO] Pinot Kafka 2.0 .................................... SUCCESS [ 48.918 s]
[INFO] Pinot Tools ........................................ SUCCESS [ 43.987 s]
[INFO] Pinot Integration Tests ............................ SUCCESS [20:04 min]

[mcvsubbu]

These are incompatible changes with earlier version of Helix. You should keep the old one at least for one release after introducing the new APIs, so as to allow users to migrate.

[mcvsubbu]

Also, when you finally remove the old APIs, do a major revision bump since that is a backward-incompatible change.

[narendly]

This particular change will be included in the next major version release of Helix.