Add Delegation Token Support to Solr
UpdateLog can miss closing transaction log objects.
Upgrade guava version to 18.0 due to Presto dependency
MapReduce contrib is using single core conf layout that no longer seems to work.
Look into using new HDFS truncate feature in HdfsTransactionLog.
Update to Hadoop 3
Remove Solr contribs: map-reduce, morphlines-core and morphlines-cell