Add tkinter App

[Soham2020]

I would like to a simple tkinter app, named Hello World. Its basic operation is to take the user's name or some texts from the user input and will show it in upper case and normal case, both are optional, means user have to select either upper case or normal case.

[prajjyadav]

or you can build time using tkinter, its simple and useful

[Soham2020]

Thank you for your suggestion. I will definitely try to implement it