Migrate MaterialUI v3.9 -> v4+

[HarisSpahijaPon]

Type: major

Describe the request
Material UI should be updated to v4+

Reason
Currently a lot of new features have been added to version 4 of Material UI. People using either example storefront or reaction-component-library will use Material UI documentation to create and style components. Following documentation from Material UI can cause bugs due to the outdated version being used in the reaction env.

Guide to migration
https://material-ui.com/guides/migration-v3/

[ghost]

MUI 4.x has been out of active development for about a year now according to @oliviertassinari. As a result, please use MUI v5 alpha or the latest version of MUI available when porting this library and ideally pair the work with a typescript refactoring or, a minimum, the introduction of type definitions as suggested in #479.