Get the MinActiveReplica from Resource Config and Idea State

[jiajunwang]

Issues

• My PR addresses the following Helix issues and references them in the PR description:

#877

Description

• Here are some details about my PR, including screenshots of any UI changes:

Read the MinActiveReplica config from both Resource Config and Idea State.

Currently, the same configuration item can be configured in both Resource Config and Ideal State. In theory, the Resource Config is the right place.
This is the first step to migrate the IdealState usage to read the Resource Config.

Tests

• The following tests are written for this issue:

TestResourceConfig.testMergeWithIdealState

• The following is the result of the "mvn test" command on the appropriate module:

Results :

Failed tests:
org.apache.helix.integration.rebalancer.CrushRebalancers.TestCrushAutoRebalanceNonRack.testLackEnoughInstances(org.apache.helix.integration.rebalancer.CrushRebalancers.TestCrushAutoRebalanceNonRack)
Run 1: PASS
Run 2: TestCrushAutoRebalanceNonRack.testLackEnoughInstances:250 » ZkClient Failed to...

Tests run: 1086, Failures: 1, Errors: 0, Skipped: 0

[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------

Rerun

Results :

Tests run: 8, Failures: 0, Errors: 0, Skipped: 0

[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------

Helix-rest:

Results :

Tests run: 99, Failures: 0, Errors: 0, Skipped: 0

[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 37.005 s
[INFO] Finished at: 2020-03-10T11:16:28-07:00
[INFO] ------------------------------------------------------------------------

Commits

• My commits all reference appropriate Apache Helix GitHub issues in their subject lines. In addition, my commits follow the guidelines from "How to write a good git commit message":
  1. Subject is separated from body by a blank line
  2. Subject is limited to 50 characters (not including Jira issue reference)
  3. Subject does not end with a period
  4. Subject uses the imperative mood ("add", not "adding")
  5. Body wraps at 72 characters
  6. Body explains "what" and "why", not "how"

Documentation (Optional)

• In case of new functionality, my PR adds documentation in the following wiki page:

(Link the GitHub wiki you added)

Code Quality

• My diff has been formatted using helix-style.xml
  (helix-style-intellij.xml if IntelliJ IDE is used)

[jiajunwang]

This PR is ready to be merged, approved by @narendly