This interface reads the manifest data from a file. The user
must supply an XInputStream when calling readManifestSequence() to recieve
a sequence of manifest entries. Each manifest entry is represented by
a sequence of PropertyValues.
This interface writes the manifest data to a file. The user
calls writeManifestSequence() with the XOutputStream to write the data to
and the sequence of manifest entries to be written passed as parameters.
Each manifest entry is represented by a sequence of PropertyValues.