vchoi_fork

[svn-r8007] Purpose:
    Bug fix

Description:
    Range check the szip 'pixels per block' against the chunk size of the
dataset when attempting to create a new dataset, since the szip library
requires the PPB to be at least the size of the fastest changing dimension
in the chunk.

Platforms tested:
    FreeBSD 4.9 (sleipnir)
    too minor for h5committest