java: add versions to certain maven plugins
java: add versions to certain maven plugins

Without them, we get this ugly warning when building:

  [WARNING]
  [WARNING] Some problems were encountered while building the effective model for kudu:kudu-client:jar:0.1.0-SNAPSHOT
  [WARNING] 'build.plugins.plugin.version' for org.apache.maven.plugins:maven-source-plugin is missing. @ line 155, column 21
  [WARNING]
  [WARNING] It is highly recommended to fix these problems because they threaten the stability of your build.
  [WARNING]
  [WARNING] For this reason, future Maven versions might no longer support building such malformed projects.
  [WARNING]

Change-Id: I40c7cb5117cc533baf42c4639038956553531018
Reviewed-on: http://gerrit.sjc.cloudera.com:8080/6500
Reviewed-by: Jean-Daniel Cryans <4bf4c125525b8623ac45dfd7774cbf531df19085@cloudera.com>
Tested-by: jenkins

helifu/kudu,helifu/kudu,cloudera/kudu,helifu/kudu,InspurUSA/kudu,cloudera/kudu,EvilMcJerkface/kudu,helifu/kudu,EvilMcJerkface/kudu,InspurUSA/kudu,EvilMcJerkface/kudu,InspurUSA/kudu,helifu/kudu,cloudera/kudu,EvilMcJerkface/kudu,EvilMcJerkface/kudu,InspurUSA/kudu,cloudera/kudu,andrwng/kudu,cloudera/kudu,andrwng/kudu,helifu/kudu,helifu/kudu,EvilMcJerkface/kudu,EvilMcJerkface/kudu,cloudera/kudu,EvilMcJerkface/kudu,andrwng/kudu,helifu/kudu,andrwng/kudu,InspurUSA/kudu,helifu/kudu,andrwng/kudu,InspurUSA/kudu,cloudera/kudu,cloudera/kudu,andrwng/kudu,EvilMcJerkface/kudu,andrwng/kudu,cloudera/kudu,InspurUSA/kudu,InspurUSA/kudu,InspurUSA/kudu,andrwng/kudu,andrwng/kudu