Create a functioning favourites list

[vdav02]

This PR primarily works towards closing #53 by implementing a favourites list specific to a user, which uses movie ID's to display information about the movies in the favourites list. Key changes and additions include...

• creating a FavouritesList component, which has an index and style file
• creating a useFavourites hook which uses the relevant endpoints to fetch the favourites list from the server, and also has within it the functionality to add and remove movies from the favourites list
• Updating the userModel to correctly interact with the favourites list in the database
• Updating the favourites page to incorporate the FavouritesList component

Next steps will be to add a button to allow users to add movies into the list, and further style the favourites list page at large

[vdav02]

Here is a screenshot of what the favourites list page currently looks like, for reference (when user testing)