Yeild a set of manifest object that parition the dumps.

        Simply adds resources/files to a manifest until their are either the
        the correct number of files or the size limit is exceeded, then yields
        that manifest.

def partition_dumps(self):
        """Yeild a set of manifest object that parition the dumps.

        Simply adds resources/files to a manifest until their are either the
        the correct number of files or the size limit is exceeded, then yields
        that manifest.
        """
        manifest = self.manifest_class()
        manifest_size = 0
        manifest_files = 0
        for resource in self.resources:
            manifest.add(resource)
            manifest_size += resource.length
            manifest_files += 1
            if (manifest_size >= self.max_size or
                    manifest_files >= self.max_files):
                yield(manifest)
                # Need to start a new manifest
                manifest = self.manifest_class()
                manifest_size = 0
                manifest_files = 0
        if (manifest_files > 0):
            yield(manifest)