For file formats like PNG, JPEG and TIFF. Eventually this should use
the OpenColorIO view transform, but this at least makes the image
closer to what it should be in most cases.
Differential Revision: https://developer.blender.org/D16482
* Replace license text in headers with SPDX identifiers.
* Remove specific license info from outdated readme.txt, instead leave details
to the source files.
* Add list of SPDX license identifiers used, and corresponding license texts.
* Update copyright dates while we're at it.
Ref D14069, T95597
* Add OutputDriver, replacing function callbacks in Session.
* Add PathTraceTile, replacing tile access methods in Session.
* Add more detailed comments about how this driver should be implemented.
* Add OIIOOutputDriver for Cycles standalone to output an image.
Differential Revision: https://developer.blender.org/D12627
