Feature Request: Adding a legend

[maximveksler]

Hi,

It would be great to add legend support for edge colors would be implemented.

In our case, we use Blue edges convention to indicate RJ45 Ethernet data transfer connectivity and Red edges convention to indicate RJ45 EtherCat controller connectivity.

This only was right now to convey this information is to add a description to each edge, which creates visual clutter.

So if diagrams have had support for creating a legend, the API I would image is add_legend(edge_type, "Description") which would draw a box with the edges and their text description.

[clayms]

have a look at #447 (comment)

and perhaps this one #433 (comment)