hdf5_ep

[svn-r1306] Changes since 19990602
----------------------

./doc/html/Datatypes.html
./test/dtypes.c
	Added documentation and tests for opaque types.

./tools/h5ls.c
	Added a `-x' or `--hexdump' argument which is not fully
	implemented (because I want to synchronize h5tools.c first)
	but which will eventually print raw data in hexadecimal format
	without any translation from disk. This would be useful for
	debugging references and VL types.

./tools/h5tools.c
	Added support for references (not quite finished yet, but
	compiles -- I wanted to sync up this file before Patrick and I
	got too far apart...)


./src/H5R.c
	Checked for error return value from H5R_get_object_type()

./src/H5A.c
./src/H5D.c
	Changed error return values from NULL to FAIL

./test/Makefile.in
./test/trefer.c
	Creates trefer1.h5 and trefer2.h5 so that the second test
	doesn't clobber the first file since the files might be useful
	for debugging.