Jupyter IFrame support

[lutzroeder]

import netron
address = netron.serve('test.onnx')
netron.widget(address, height=800)

See #1346

[mattcattb]

Has this been implimented?

[vtemplier]

it seems to be working now.

I leave it to @lutzroeder to close this issue, if it is solved correctly.

PS: Don't forget to add browse=false to avoid opening another window to view your model.