Fix MultiDiGraph() docstring to reflect input flexibility
Fix MultiDiGraph() docstring to reflect input flexibility

The existing documentation on the MultiDiGraph() constructor function says that it can only take "an edge list or a NetworkX graph object" as well as a few third-party formats. This isn't true, since the data is just passed to the to_networkx_graph() function, which can actually accept a far wider variety of input formats - including dict of dicts and dict of lists.
JamesClough/networkx,NvanAdrichem/networkx,cmtm/networkx,jfinkels/networkx,goulu/networkx,Sixshaman/networkx