vchoi_fork

[svn-r8126] Purpose:
    Bug fix/optimization

Description:
    Address slowdown in MPI-I/O file metadata operations that was introduced
mid-stream.  We now _require_ a POSIX compliant parallel file system for the
MPI-I/O file driver (as well as for the MPI-POSIX file driver).
    Also optimized file open operation when the file is being created by
reducing the number of collective & syncronizing calls.
    Additionally, refactor the MPI routines into a common place, eliminating
duplicated code.

Platforms tested:
    FreeBSD 4.9 (sleipnir) w/parallel
    h5committest