Along the way, added a bunch of diagnostic output in the HDFS calls, which
only shows up at verbosity >= 4. I'll probably remove this stuff before
merging with master. Also, there's an #ifdef'ed-out sleep() in place,
which I used to attach gdb to a running MPI task. I'll get rid of that
later, too.
Also, added another hdfs-related parameter to the IOR_param_t structure;
hdfs_user_name gets the value of the USER environment-variable as the
default HDFS user for connections. Does this cause portability problems?
28c94f8875