Suggestion: Colab notebook enhancements

[take2rohit]

There is a problem of paths in colab.

1. Colab doesnt know what is ../../bar we need to rather specify Monk/foo/bar
2. Instead of adding paths like relative + '\' + final + '\' we should rather use os.path.join(relative,final). This is because sometimes it had thrown error even if i entered correct path (that slash caused problem)
3. Since most of the code base is based on tf 1.x its best to specify %tensorflow_version 1.x at starting of notebook (Since colab will make tf2 default very soon)

[abhi-kumar]

2. That's a good point. Using os.path.join is a better option than using a string to do the same.
   Please make appropriate changes to notebooks and core code and raise multiple PRs.

For the colab points, I will specify a few things soon.

[abhi-kumar]

Closing the Issue. Solution provided