Filters should not reset after a refresh/new session

[OrdinaryGecko]

When I refresh the page, my chosen filters like patterns, difficulty etc. gets reset. Is it possible to retrieve last used filters?

[seanprashad]

Hey! 👋🏽 I think this is doable - another user had requested this feature back in #87. I'll open this up to contributors since I think we can save/load filters from localStorage, like how we do for which questions are checked off!

[steviekong]

This PR should resolve the issue