HADOOP-19203. WrappedIO BulkDelete API to raise IOEs as UncheckedIOExceptions (#6885)



* WrappedIO methods raise UncheckedIOExceptions
*New class org.apache.hadoop.util.functional.FunctionalIO
 with wrap/unwrap and the ability to generate a
 java.util.function.Supplier around a CallableRaisingIOE.

Contributed by Steve Loughran
4 files changed