FrontEnd: Class Names in front of every component and Container

[simonreddy2001]

Description

Fixed all components and containers class names. so you can get proper result of css and no unnecessary styles by same name or tag between any components/containers. Added "keep shopping" story button. Please provide a short summary explaining what this PR is about.

Fixes #259

How to test?

npm run dev npm run storybook Please provide a short summary how your changes can be tested?

Checklist

• [x] I have performed a self-review of my own code
• [x] I have followed the name conventions for CSS Classnames and filenames, Components names and filenames, Style filenames, if you are in doubt check the the project README.MD and here https://github.com/HackYourFuture-CPH/curriculum/blob/master/review/review-checklist.md
• [x] I have commented my code, particularly in hard-to-understand areas, if you code was simple enough mark the box anyway
• [x] I have made corresponding changes to the documentation, if you code was simple enough mark the box anyway
• [x] This PR is ready to be merged and not breaking any other functionality