hdf5_ep

[svn-r19745] Description:
	Bring r19743-19744 from trunk to 1.8 branch:

	Correct tests to use native datatypes consistently, and also to use
"normal" methods for performing collective I/O.  Also, minor cleanups for
zeroing out buffers, etc.

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