ACCUMULO-1932 Make the agitator a little more robust, not relying on start-dfs.sh to minimize the amount of chatter
across the network to only restart one datanode.
ACCUMULO-1932 Add note to continuous-ingest README that agitator needs to be run as `root`.
Merge branch '1.5.1-SNAPSHOT' into 1.6.0-SNAPSHOT
Merge branch '1.6.0-SNAPSHOT'