Update README.md

README: add Possible future improvements/functionalities

README: minor changes

Update README.md

Update README.md

Simplify login connection logic

Fix logout function bug

Add log out button to user_sidebar

Update customer_rank function: write a different message for #1 customer

Update updatecart() function: add option to add more of the same product type when it's already in the cart

Add remove from cart functionality to showcart function

Update app.py

Update functions.py

Move buttons and forms in home page to functions in function.py

Organise session set up