This task is to simplify the HBase dependencies:
a) We don't need to specify the Solr jar as it gets picked up from the audit module.
b) We don't need to specify the HDFS jar as we don't bundle it in the distribution - the jar is picked up from HBase itself.
c) The 2.7.1 Hadoop dependencies in the HBase pom should be removed - instead we should just pick up the Hadoop dependencies required for testing from the Hadoop version that ships with HBase.
This work means that the HBase module compiles + tests work correctly when we upgrade to Hadoop 3.0.0.
No changes to the distribution jars. Tested HDFS + Solr auditing still works as expected with the plugin.