ACCUMULO-3193 use a thread pool to jam more requests into the NN, which will hopefully compete better with the other NN requests
Merge branch 'master' of https://git-wip-us.apache.org/repos/asf/accumulo
ACCUMULO-3204 Remove old, unused classes
ACCUMULO-3197 Remove deprecated items from Instance

  Partially addresses ACCUMULO-3199 by removing the getConfiguration() method
  from Instance, which is prone to misuse.
ACCUMULO-3197 Remove deprecated code