Add KIP-235 implementation

[anchitj]

Changes done

Add functionality to support KIP-235. Kept the implementation similar to the Java client in apache/kafka#4485

• Added a new config boolean property resolve.canonical.bootstrap.servers.only. User should enable this if they are specifying DNS aliases in the bootstrap servers.
• If the above property is enabled, an address -> A records -> PTR lookup is performed before the brokers are added for each address in the broker list.

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Testing

Manually. Adding automated test will probably need some sort of integration with a mock DNS server within librdkafka.

Steps:

1. Setup Kerberos environment from kafka-docker-playground.
2. Add another container c2 in the docker-compose with contents and Dockerfile.
3. Start the containers using ./../../scripts/cli/playground run -f start.sh --disable-ksqldb --disable-control-center.
4. SSH into the c2 container, and in the /etc/hosts file add two new lines, replacing 172.18.0.5 with the actual address of the broker container.

172.18.0.5 broker.kerberos-demo.local
172.18.0.5 randomExample.com

5. Use client code client.c which is using randomExample.com:9092 and client.dns.lookup set to resolve_canonical_bootstrap_servers_only to connect with the Kerberos protected Kafka broker.
6. If client.dns.lookup is not set, the client is unable to connect with the broker.

[anchitj]

Semaphore PR corresponding - #4307

[pranavrth]

Update supported kips section as well here

[anchitj]

Updated the supported KIPs section as well

[anchitj]

Verified from that all the tests except 0017_compression work when running individually from make run_seq

| 0017_compression                         |     FAILED | 888.679s | test_dr_msg_cb():1967: Message delivery (to rdkafkatest_rnd55cf09950b7e4136_snappy [0]) failed: expected Success, got Unknown broker error

This above error is occurring even when running with the latest master, so is unrelated to the PR.

[pranavrth]

LGTM! Nice Work.

Just a couple of points we need to confirm with @emasab.

[pranavrth]

Correct the description of the PR.

[emasab]

LGTM too, thanks Anchit!