hdf5_msb

[svn-r12148] Purpose:
Add tests for optional APIs to support collective chunk IO

Description:

In order to test whether library picks up the user's options,
The number of chunks need to be varied for different processes,
Selection of the number of processes selected in one chunk also
need to be varied.
Solution:
Create two cases,

1. Each chunk only selected by one unique process, this case
library should use independent for collective call.
2. One-third of the processes occupies the top half of the whole domain,
   The rest of the processes occupies the lower half of the domain.
   The total number of chunk is a fixed number 8.

Platforms tested:
Linux 2.4 with mpich 1.2.6(only)

Since I only checked in the code that handles the selection, haven't added any new tests yet. So it won't affect any platforms.


Misc. update: