hdf5_ep

[svn-r19499] Description:
	Bring r19498 from trunk to 1.8 branch:

        Optimize the vector-vector memcpy() routine even further, for a total
of ~2x speedup.  :-)

        Make a generic vector-vector operation routine and convert other
vector-vector read & write routines to use generic routine instead of multiple
copies of the basic algorithm.

Tested on:
        FreeBSD/32 6.3 (duty) in debug mode
	(h5committested on trunk)