Merge pull request #2095 in HDFFV/hdf5 from ~NFORTNE2/hdf5_naf:hdf5_1_12 to hdf5_1_12
* commit 'aaf67f1d3eceb9c214f013bdf1b3dc06b29bb174':
Add RELEASE.txt note for H5Sselect_project_interesection
Implement public H5Sselect_project_intersection(). Updated internal algorithm to (optionally) avoid sharing selection data structures. Tested internal code (including with valgrind) by setting VDS code to avoid sharing selection, has since been changed to share selection for performance, so this code is not yet tested in regression tests. API has not been tested.
