hdf5_ep

[svn-r22174] Port r22173 from trunk to 1.8 branch

Purpose: Fix HDFFV-7762

Description:
When copying an object with attribute creation order tracked, the attribute
creation order was not copied correctly to the destination file, causing an
error if the creation order was also indexed (due to attempting to insert
duplicate keys) or incorrect creation orders otherwise.  Fixed to copy the
creation order correctly.

Also fixed the attribute character set not being copied, and fixed an issue
where an attribute opened with H5Aopen (or similar, but not by_idx), from an
object using the latest format but without creation order being tracked, would
always report the creation order as 0 (and marked as valid).

Tested: jam, koala, ostrich (h5committest), durandal