[SPARK-4632][Streaming] Upgrade MQTT dependency to latest version

[tdas]

MQTT client 0.4.0 was removed from the Eclipse Paho repository, and hence is breaking Spark build. This upgrades the version of MQTT client. This is an alternative approach to #3485 for unblocking Spark 1.2 release.

Note that whether the MQTT functionality is still working after this upgrade is not really being tested as the unit test does not actually transfer data. So only API compatibility is ensured. Adding a real unit test has been noted as another JIRA (https://issues.apache.org/jira/browse/SPARK-4631). For the purpose of unblocking Spark 1.2 release, I am ready to make this upgrade even with the slight risk of breaking MQTT functionality.

[SparkQA]

Test build #23909 has started for PR 3487 at commit 9b1afe0.

• This patch merges cleanly.

[sryza]

nit: version should be indented at the same level as artifactId

[tdas]

Arrgggh .. my bad. should fix existing bug.

[SparkQA]

Test build #23910 has started for PR 3487 at commit 4f5e53c.

• This patch merges cleanly.

[SparkQA]

Test build #23909 has finished for PR 3487 at commit 9b1afe0.

• This patch passes all tests.
• This patch merges cleanly.
• This patch adds no public classes.

[AmplabJenkins]

Test PASSed.
Refer to this link for build results (access rights to CI server needed):
https://amplab.cs.berkeley.edu/jenkins//job/SparkPullRequestBuilder/23909/
Test PASSed.

[SparkQA]

Test build #23910 has finished for PR 3487 at commit 4f5e53c.

• This patch passes all tests.
• This patch merges cleanly.
• This patch adds no public classes.

[AmplabJenkins]

Test PASSed.
Refer to this link for build results (access rights to CI server needed):
https://amplab.cs.berkeley.edu/jenkins//job/SparkPullRequestBuilder/23910/
Test PASSed.

[JoshRosen]

I think we can close this now, since #3495 was merged in (I like this PR's description better, though, so I wish this version had been merged :( ).

[pwendell]

Yeah let's close this issue.