This box within a Media Box declares the process by which the media-data in
the track is presented, and thus, the nature of the media in a track. For
example, a video track would be handled by a video handler.

This box when present within a Meta Box, declares the structure or format of
the 'meta' box contents.

There is a general handler for metadata streams of any type; the specific
format is identified by the sample entry, as for video or audio, for example.
If they are in text, then a MIME format is supplied to document their format;
if in XML, each sample is a complete XML document, and the namespace of the
XML is also supplied.

@author Alexander Simm

When present in a media box, the handler type is an integer containing
one of the following values:

• 'vide': Video track


• 'soun': Audio track


• 'hint': Hint track


• 'meta': Timed Metadata track

When present in a meta box, it contains an appropriate value to indicate
the format of the meta box contents. The value 'null' can be used in the
primary meta box to indicate that it is merely being used to hold
resources.

@return the handler type

The name gives a human-readable name for the track type (for debugging
and inspection purposes).
return  the handler type's name