ACCUMULO-3297 allow metadata table reads even if all files have been allocated
ACCUMULO-3297 merge 1.6 to master
ACCUMULO-3147 Refactor ReplicationTable constants
ACCUMULO-3147 Fix formatting issues on changed files
ACCUMULO-3147 Create replication table at initialize
ACCUMULO-3147 Migrate to built-in replication table

  Migrate to all replication code to the built-in system-managed replication
  table instead of the user-space one. Ensure all replication-related tests
  pass. Also fix a small bug in Mock which threw an exception when using
  deleteRows with null start and end rows.