Merge pull request #3824 from pbalcer/obj-ulog-zero

src/libpmemobj/memops.c

src/libpmemobj/ulog.c

src/libpmemobj/ulog.h

src/test/obj_memops/obj_memops.c

src/test/obj_persist_count/out0.log.match

src/test/obj_persist_count/out1.log.match