`core` should only be used for legacy cli tools and tools that require
access to `core` classes instead of communicating via the kafka protocol
(typically by using the client classes).
Summary of changes:
1. Convert the command implementation and tests to Java and move it to
the `tools` module.
2. Introduce mechanism to capture stdout and stderr from tests.
3. Change `kafka-metadata-quorum.sh` to point to the new command class.
4. Adjusted the test classpath of the `tools` module so that it supports tests
that rely on the `@ClusterTests` annotation.
5. Improved error handling when an exception different from `TerseFailure` is
thrown.
6. Changed `ToolsUtils` to avoid usage of arrays in favor of `List`.
Reviewers: dengziming <dengziming1993@gmail.com>
Add `MetadataQuorumCommand` to describe quorum status, I'm trying to use arg4j style command format, currently, we only support one sub-command which is "describe" and we can specify 2 arguments which are --status and --replication.
```
# describe quorum status
kafka-metadata-quorum.sh --bootstrap-server localhost:9092 describe --replication
ReplicaId LogEndOffset Lag LastFetchTimeMs LastCaughtUpTimeMs Status
0 10 0 -1 -1 Leader
1 10 0 -1 -1 Follower
2 10 0 -1 -1 Follower
kafka-metadata-quorum.sh --bootstrap-server localhost:9092 describe --status
ClusterId: fMCL8kv1SWm87L_Md-I2hg
LeaderId: 3002
LeaderEpoch: 2
HighWatermark: 10
MaxFollowerLag: 0
MaxFollowerLagTimeMs: -1
CurrentVoters: [3000,3001,3002]
CurrentObservers: [0,1,2]
# specify AdminClient properties
kafka-metadata-quorum.sh --bootstrap-server localhost:9092 --command-config config.properties describe --status
```
Reviewers: Jason Gustafson <jason@confluent.io>