Registers a parameter to the link.
Deprecated since version v2.0.0: Assign a
Parameter object directly to an
an initialization scope
instead. For example, the following code
link.add_param('W', shape=(5, 3))
can be replaced by the following assignment.
link.W = chainer.Parameter(None, (5, 3))
The latter one is easier for IDEs to keep track of the attribute’s