KAFKA-4417: Update build dependencies for 0.10.2 cycle

[ijuma]

Notes on the updates:

• Gradle to 3.2: better incremental build and faster IDE import times (https://docs.gradle.org/3.2/release-notes)
• zkclient to 0.10: it now uses slf4j-api instead of log4j
• zookeeper to 3.4.9: a few important bug fixes (http://zookeeper.apache.org/doc/r3.4.9/releasenotes.html)
• jackson to 2.8.5: lots of updates (https://github.com/FasterXML/jackson/wiki/Jackson-Release-2.6, https://github.com/FasterXML/jackson/wiki/Jackson-Release-2.7, https://github.com/FasterXML/jackson/wiki/Jackson-Release-2.8)
• jersey to 2.24: bug fixes (https://jersey.java.net/release-notes/2.23.html, https://jersey.java.net/release-notes/2.24.html)
• jopt to 5.0.3: minor improvements, the major version bump is due to requiring Java 7 instead of 6 (https://pholser.github.io/jopt-simple/changes.html)
• argparse4j to 0.7.0: minor tweaks and improvements (https://github.com/tatsuhiro-t/argparse4j/blob/argparse4j-0.6.0/NEWS, https://github.com/tatsuhiro-t/argparse4j/blob/argparse4j-0.7.0/NEWS)
• Gradle plugins
• bcpkix to 1.55: quite a few additions, but nothing that matters to us (http://www.bouncycastle.org/releasenotes.html)

[ijuma]

Started a system tests build: https://jenkins.confluent.io/job/system-test-kafka-branch-builder/613/console

[ijuma]

There was one system test failure, but this test fails transiently from time to time: StreamsSmokeTest.test_streams.

@ewencp, maybe you can review this when you have time.

[ewencp]

LGTM