Display message for any invalid action on the graph

[anand-2020]

Is your feature request related to a problem? Please describe.
Currently, if the user wants to perform an action on the graph which is not valid for that particular graph, nothing happens. But in addition to this, it would be better if the user gets notified that the requested action can not be performed along with the reason for the same.

Describe the solution you'd like
The message should appear on bottom right of the screen and should fade out after few seconds. The message must contain the reason for the requested action being invalid. Try to use Material UI Snackbar for implementing this.

Additional context
Here, the invalid actions could be trying to add an edge between a pair of vertices when an edge already exists between them, action for deleting an edge which doesn't exist, etc.