vchoi_fork

[svn-r1418]     Modified H5Tconvert to require a dataset transfer property list ID as the
final parameter (so that VL datatypes have a way to pass in the custom memory
allocation routines).
    Fixed a conversion bug when VL fields were part of a compound datatype that
was causing the no-op conversion routine to be used instead of the vlen routine.
    Added the H5Pset_vlen_mem_manager and H5Pget_vlen_mem_manager routines to
allow users to provide their own custom memory allocation routines for VL data
read in from the file and reclaimed with H5Dvlen_reclaim.
    Finished coding on H5Dvlen_reclaim so it works now.