hdf5_ep

[svn-r2587] Purpose:
    Bug fix (sorta)
Description:
    When the stride and block size of a hyperslab selection are equal, the
    blocks that are selected are contiguous in the dataset.  Prior to my
    hyperslab optimizations, this situation used to be detected and somewhat
    optimized to improve performance.  I've added more code to optimize for
    this situation and integrated it with the new hyperslab optimization that
    weren't very efficient for that case as they should have been.
Solution:
    Detect contiguous hyperslab selections (i.e. block size in a dimension is
    the same as the stride in that dimension) and store the optimized,
    contiguous version of that hyperslab.  We also store the original, un-
    optimized version of the hyperslab to give back to the user if they query
    the hyperslab selection they just made.
Platforms tested:
    FreeBSD 4.1