hdf5_der

[svn-r24424] 
As part of rewiring single-dset H5Dread/H5Dwrite via multi-dset Read/Write path functions, cutoff some duplicated single-dset Read/Write path functions as result of the rewiring work since the pathway now go through multi-dset Read/Wrtie path functions instead.

Note:
Debugging code and extra code are still remained for debug and back-trace purpose.
Extra code will be cleaned up at wrapping up stage later when all things work.
Debugging messages are turned off, so there is no debugging print outs when run
tests.