OpenImageIO v2.3.11.0

Release 2.3.11 (1 Jan 2022) -- compared to 2.3.10

• JPEG2000: enable multithreading for decoding (if using OpenJPEG >= 2.2)
  and encoding (if using OpenJPEG >= 2.4). This speeds up JPEG-2000 I/O
  by 3-4x. #2225
• TIFF: automatically switch to "bigtiff" format for >4GB images. #3158
• Security: New global OIIO attributes "limits:channels" (default: 1024) and
  "limits:imagesize_MB" (default: 32768, or 32 GB) are intended to reject
  input files that exceed these limits, on the assumption that they are either
  corrupt or maliciously constructed, and would, if read, lead to absurd
  allocations, crashes, or other mayhem. Apps may lower or raise these limits
  if they know that a legitimate input image exceeds these limits. Currently,
  only the TIFF reader checks these limits, but others will be modified to
  honor the limits over time. #3230
• TextureSystem: enhance safety/correctness for untiled images that exceed
  2GB size (there was an integer overflow problem in computing offsets within
  tiles). #3232
• Cleanup: Get rid of an obsolete header c-imageio.h that was experimental
  and the functions declared therein were not implemented in this release.
  #3237
• Build: rely on env variable "OpenImageIO_CI" to tell us if we are running in
  a CI environment, not the more generic "CI" which could be set for other
  reasons in some environments. #3211
• Build: Improvements in how we find OpenVDB. #3216
• Build: If CMake variable BUILD_TESTING is OFF, don't do any automatic
  downloading of missing test data. #3227
• Dev: Add Strutil::edit_distance(). #3229
• Docs: Clean up intra-document section references, new explanations about
  input and output configuration hints, more code examples in both C++ and
  Python (especially for the ImageInput and ImageOutput chapters). #3238 #3244