Flexible OCIO config file options

Blender comes with its own OCIO config files under datafiles\colormanagement . Currently, if you want to use ACES (for example) you must copy some ACES config files into this directory (destructively altering the Blender installation) or point Blender to your preferred OCIO configuration using the standard OCIO environment variable. This latter option can currently be implemented by permanently setting your system's OCIO environment variable (affecting all programs on your system, probably not what you want) or writing a wrapper script to set the variable for launching Blender (clunky when you have several Blender versions installed).

Here I am proposing some additional options I would like to have, sorted from easiest to hardest to implement

• support an environment variable called BLENDER_OCIO which supercedes the OCIO variable (this suggestion from @Ginurx on his extremely useful ACES github repo )
• provide an option to choose the OCIO configuration folder in the Blender configuration "File Paths" pane
• optionally embed the OCIO config files into the blender file itself as a datablock (similar to how images can be embedded in the blender file). This would enable render farms like Sheepit to support ACES, a genuinely useful thing