The issue:
Getting the message "Sorry, something went wrong. Reload?" when viewing an *.ipynb on a GitHub blob page.
Probably a problem with the GitHub notebook viewing tool - sometimes github fails to render the ipynb notebooks, I believe that is some temporary (and recurring) issue with their backend.
A workaround:
Try to open that notebook that you want using nbviewer online, you don't need to install it.
Open "https://nbviewer.jupyter.org/" Paste the link to your notebook, (e.g. "https://github.com/KumarVishwesh1992/DataScience_DeepLearning_MachineLearning/blob/master/Classification/DecisionTree.ipynb") there and then you get.