Display issues when adding an endpoint via widget

[aggFTW]

Look at

[pranayhasan]

@aggFTW I'm taking up fixing this issue.
I opened a PR #368 which fixes this. I updated ipywidgets to 7.0.0 version which is still in alpha, and waiting on them to release it so as to have a password widget. notebook is updated to use 5.0.0 for the recent output_area changes which addresses issues in displaying plots.