vchoi_fork

[svn-r7559] Purpose:
    Add feature

Description:
    Add H5Fget_freespace() routine, to check the amount of free space in a
    file.  This information is only valid until the file is closed currently,
    however (until we start recording the free space information in the file
    itself).

Platforms tested:
    FreeBSD 4.9 (sleipnir)
    h5committest