hdf5_der

[svn-r19765] Purpose:

    fix a few minor issues related to flush/refresh code

Description:

    - Replaced the globality macros with an enum typedef, to
      better encapsulate of the values that can be assigned
      to the variable.
    - Combined 'tag' and 'globality' properties into a single
      property by creating a new structure housing both values,
      since they are always accessed at the same time anyways.
    - Added an extra parameter check to H5Tflush/H5Trefresh
      routines to make sure the supplied datatype is a committed
      datatype.
    - Renamed and reworked some code to move "metadata" (H5AC)
      specific things out of the generic cache (H5C) level of code.

Tested:

    h5committest