Creates a new gstreamer.Caps as a copy of the old caps. The new caps will have a
refcount of 1, owned by the caller. The structures are copied as well.
Note that this function is the semantic equivalent of a Caps.ref
followed by a Caps.makeWritable. If you only want to hold on to a
reference to the data, you should use Caps.ref.
When you are finished with the caps, call Caps.unref on it.
the new gstreamer.Caps