Log Message:
Changes 3.1.0:

OUTPUT CHANGES:

- Output numbers in 3-digit groups by default (e.g. 1,234,567).  See the
  --human-readable option for a way to turn it off.  See also the daemon's
  "log format" parameter and related command-line options (including
  --out-format) for a modifier that can be used to request digit-grouping
  or human-readable output in log escapes. (Note that log output is
  unchanged by default.)

- The --list-only option is now affected by the --human-readable setting.
  It will display digit groupings by default, and unit suffixes if higher
  levels of readability are requested.  Also, the column width for the size
  output has increased from 11 to 14 characters when human readability is
  enabled.  Use --no-h to get the old-style output and column size.

- The output of the --progress option has changed:  the string "xfer" was
  shortened to "xfr", and the string "to-check" was \ 
shortened to "to-chk",
  both designed to make room for the (by default) wider display of file
  size numbers without making the total line-length longer.  Also, when
  incremental recursion is enabled, the string "ir-chk" will be used
  instead of "to-chk" up until the incremental-recursion scan is done,
  letting you know that the value to check and the total value will still
  be increasing as new files are found.

- Enhanced the --stats output: 1) to mention how many files were created
  (protocol >= 28), 2) to mention how many files were deleted (a new line
  for protocol 31, but only output when --delete is in effect), and 3) to
  follow the file-count, created-count, and deleted-count with a subcount
  list that shows the counts by type.  The wording of the transferred count
  has also changed so that it is clearer that it is only a count of regular
  files.

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