Updated benchmark results.
  * changes UnsupportedOperationException to assert.
 * Removed spurious override of convert method in map reduce demo
 * Throw exception and gave appropriate error message when closing resources in teardown for
   input and ouput operators
 * Handled edge cases for rolling files
 * Changed append property to define how files are treated when discovered by the operator. If
   the operator finds a previously unseen file and append is true, then that file is appended
   to. If the operator finds a previously unseen file and append is false, then that file is
   overwritten.
Merge branch 'MLHR-1415_pull' into MLHR-1415_pull_test