are not already existing. Add edges between every two nodes
corresponding to a pair of successive modules in the arguments.
+Calling it with n > 2 arguments is strictly equivalent to calling it
+n-1 times on the pairs of successive arguments.
+
##nn.DAG:setInput(i)##
Defines the content and structure of the input. The argument should be
See the torch documentation.
+--
*Francois Fleuret, Jan 13th, 2017*