human_num() and human_dnum() functions, which both honor the
new --human-readable option.

output numbers in human-readable units if the --human-readable
option was specified.

cleanup_fname to NULL.

- Got rid of a superfluous newline.

from column 0.

- Indent the "oom:" and "skip_filters:" labels away from column 0.

specified.

This stops computing useless checksums during the delete scan
when --checksum (-c) was specified.

right value for the current protocol_version over and over.

only once instead of over and over again.

just remove the partial-dir file.

efficient by removing the need for a MAXPATHLEN buffer on the
stack of delete_item().

in the flist (which was changed to a countdown of files to check)
so that it's clearer what the numbers mean.

recursion by eliminating the need for a MAXPATHLEN buffer in
send_if_directory().  Also improved a few variable names in
send_file_list().