OpenImageIO v2.5.12.0

Release 2.5.12.0 (June 1, 2024) -- compared to 2.5.11.0

• exr: Add IOProxy support for EXR multipart output #4263 #4264 (by jreichel-nvidia)
• pnm: Improvements to pnm plugin: support for uint16 and 32-float, "pnm:bigendian" and "pnm:pfmflip" controls for output. #4253 (by Vlad (Kuzmin) Erium)
• ImageBuf: Improve behavior of IB::nsubimages and other related fixes #4228
• simd.h: Fix longstanding problem with 16-wide bitcast for 8-wide HW #4268
• strutil.h: Add Strutil::eval_as_bool #4250
• tests: Add new heif test output #4262
• tests: Fix windows quoting for test #4271
• build: More warning elimination for clang18 #4257
• build: Add appropriate compiler defines and flags for SIMD with MSVC #4266 (by Jesse Yurkovich)
• build: Gcc-14 support, testing, CI #4270
• docs: Fix stray references to the old repo home #4255