including the merge of `hdffv/hdf5/develop`, back to the branch that Vailin and
I share.
Now I need to put this branch on a fork with a less confusing name than
vchoi_fork!
1) Check for valid object header version for a refcount messge
2) Check for invalid fill value size
3) Check for invalid dimension size in a layout message
4) Add --enable-error-stack option to h5stat
5) Add error checks to h5stat.c
6) Add tests to h5stat and h5dump