Added support for visualising the Tree

[jalotra]

Solves #36

How to test, have written a sample test in :

python3 -m raptor.tests.visualise_tree_test

Example Image generated with test :

[jalotra]

@parthsarthi03 please review as and when you get waqt

[jalotra]

@parthsarthi03 Reminding

[parthsarthi03]

I'd want to avoid adding extra dependencies. Rest looks good, could we also have a readme section on how to visualize.

[parthsarthi03]

Can we please keep the extra dependencies added to a minimum requirements.txt? It might be better to have separate instructions to install the libraries needed for the visualization.

[jalotra]

ack, I have added support to download the needed igraph and plotly when the user needs it.

[jalotra]

I'd want to avoid adding extra dependencies. Rest looks good, could we also have a readme section on how to visualize.

Have added instructions in both Readme and demo.ipynb on how to use visualisation using plotly.

[jalotra]

@parthsarthi03 please look once whenever free

[parthsarthi03]

@jalotra Thanks for the great work! I was running it for the sample story, but there seems to be a bug, the root index 34, is becoming a parent note of the -1 index node (see screenshot below).

Also, not a blocker but a great feature to have would be layer no. displayed with a different color for each layer.

[jalotra]

hello hello, this is a plotly thing where they sometimes visually mark up the child on top if space is limited, but rest assured that node is child.