hdf5_der

[svn-r23775] Implement SWMR-5:
Implemented use case 1.9: Appending n-1 dimensional planes

Adding the option "-y" which allows chunks to be thicker
(more than 1 plane). This supports use case 1.9 which have chunks
of multiple planes but writing is still appending one plane at a time.
Using -y with "use_append_chunk", would provide the use case
of writing a plane to a partial chunk.
Using -y with "use_append_mchunks", would provide the use case
of writing a plane to multiple partial chunks.

Also added the option -n which specifies how many planes to write
instead of the defaults of chunksize number of planes. This allows
the final dataset to be other than a cube.

test/use_append_mchunks.c:
test/use_common.c:
test/use.h:
test/use_append_chunk.c:
I also overhauled code in use_append_mchunks and use_append_chunk:
    1. creating a set_parameter() to customize individual use case;
    2. combine the create_uc_file(), read_uc_file() and write_uc_file()
       of both use cases appending one plane per chunks and one plane per
       multiple chunks.  Moved these combined create/read/write functions
       into use_common.c to make future modification and maintence easier.
test/test_usecases.sh.in:
Added a simple test to demonstarte how to use -y to run use case 1.9.

Tested: h5committest, except cmake, passed. Hand tested in Koala for various options.