Roll version of gsutil to 4.15.

third_party/gsutil/CHANGES.md

+Release 4.15 (release date: 2015-09-08)
+=======================================
+Bug Fixes
+---------
+- Fixed an OverflowError in apitools that caused download
+  failures for large files on 32-bit machines.
+- Removed unnecessary sending of range headers for downloads when
+  using the XML API.
+- Fixed a bug that caused perfdiag to report extremely high throughput
+  when the -p flag was unspecified and exactly one of the -c or -k flags
+  were specified.
+- Fixed a ValueError that occurred on Python 2.6 with sliced object downloads.
+
+Other Changes
+-------------
+- HTTP connections for downloads and uploads in the JSON API are now
+  re-used per-thread.
+- When gsutil's automatic update feature prompts and the user
+  chooses to update, gsutil will now exit with status code 1 after
+  updating (because the original command was not executed).
+- The cp -A flag is disabled when using gsutil -m to ensure that
+  ordering is preserved when copying between versioned buckets.
+
+Release 4.14 (release date: 2015-08-24)
+=======================================
+New Features
+------------
+- Implemented Sliced Object Download feature.
+  This breaks up a single large object into multiple pieces and
+  downloads them in parallel, improving performance. The gsutil cp, mv
+  and rsync commands now use this by default when compiled crcmod
+  is available for performing fast end-to-end integrity checks.
+  If compiled crcmod is not available, normal object download will
+  be used. Sliced download can be used in conjunction with the global -m
+  flag for maximum performance to download multiple objects in
+  parallel while additionally slicing each object.
+  See the "SLICED OBJECT DOWNLOAD" section of "gsutil help cp" for
+  details.
+  Note: sliced download may cause performance degradation for disks
+  with very slow seek times. You can disable this feature by setting
+  sliced_object_download_threshold = 0 in your .boto configuration file.
+- Added rthru_file and wthru_file test modes to perfdiag, allowing
+  measurement of reads and writes from a disk. This also allows
+  measurement of transferring objects too large to fit in memory.
+  The size restriction of 20GiB has been lifted.
+- perfdiag now supports a -p flag to choose a parallelism strategy
+  (slice, fan, or both) when using multiple threads and/or processes.
+
+Bug Fixes
+---------
+- Fixed an IOError that could occur in apitools when acquiring credentials
+  using multiple threads and/or processes on Google Compute Engine.
+- Fixed a bug where rm -r would attempt to delete a nonexistent bucket.
+- Fixed a bug where a default object ACL could not be set or changed to empty.
+- Fixed a bug where cached credentials corresponding to an old account could
+  be used (for example, credentials associated with a prior .boto
+  configuration file).
+- Fixed a bug in apitools for retrieving byte ranges of size 1 (for example,
+  "cat -r 1-1 ...")
+- Fixed a bug that caused the main gsutil process to perform all work leaving
+  all gsutil child processes idle.
+- Fixed a bug that caused multiple threads not to be used when
+  multiprocessing was unavailable.
+- Fixed a bug that caused rsync to skip files that start with "." when the
+  -r option was not used.
+- Fixed a bug that caused rsync -C to bail out when it failed to read
+  a source file.
+- Fixed a bug where gsutil stat printed unwanted output to stderr.
+- Fixed a bug where a parallel composite upload could return a nonzero exit
+  code even though the upload completed successfully. This occurred if
+  temporary component deletion triggered a retry but the original request
+  succeeded.
+- Fixed a bug where gsutil would exit with code 0 when both running in
+  debug mode and encountering an unhandled exception.
+- Fixed a bug where gsutil would suggest using parallel composite uploads
+  multiple times.
+
+Other Changes
+-------------
+- Bucket removal is now supported even if billing is disabled for that bucket.
+- Refactored Windows installs to no longer use any multiprocessing module
+  functions, as gsutil has never supported multiple processes on Windows.
+  Multithreading is unaffected and still available on Windows.
+- All downloads are now written to a temporary file with a "_.gstmp" suffix
+  while the download is still in progress.
+- Re-hashing of existing bytes when resuming downloads now displays progress.
+- Reduced the total number of multiprocessing.Manager processes to two.
+- The rm command now correctly counts the number of objects that could
+  not be removed.
+- Increased the default retries to match the Google Cloud Storage SLA.
+  By default, gsutil will now retry 23 times with exponential backoff up
+  to 32 seconds, for a total timespan of ~10 minutes.
+- Improved bucket subdirectory checks to a single HTTP call. Detection of
+  _$folder$ placeholder objects is now eventually consistent.
+- Eliminated two unnecessary HTTP calls when performing uploads via
+  the cp, mv, or rsync commands.
+- Updated documentation for several topics including acl, cache-control,
+  crcmod, cp, mb, rsync, and subdirs.
+- Added a warning about using parallel composite upload with NEARLINE
+  storage-class buckets.
+
 Release 4.13 (release date: 2015-06-03)
 =======================================
 New Features
 ------------
 - Added -U flag to cp and rsync commands to allow skipping of unsupported
   object types.
 - Added support for Google Developer Shell credentials.
 
 Bug Fixes
 ---------
@@ skipping 1564 matching lines @@
     administrator to install gsutil in a central location, using the Python
     distutils facility. This mode is supported only on Linux and MacOS.
   - RPM mode (new). A RedHat RPM can be built from the gsutil.spec.in file
     in the unpacked gsutil directory, allowing it to be installed as part of
     a RedHat build.
 
 - Note: v2.0 is the first numbered gsutil release. Previous releases
   were given timestamps for versions. Numbered releases enable downstream
   package builds (like RPMs) to define dependencies more easily.
   This is also the first version where we began including release notes.