Update to use expo web

[EvanBacon]

Soon... Setting this as a reminder. It might even make sense to close this in favor of a general example that works everywhere.

[ericvicenti]

Cool. What expo web modules do you have in mind for this example? Would be nice to keep things simple here, but I’d be happy to see anything that can reduce boilerplate in this repo!

[EvanBacon]

Brent just pointed out that this example is meant for usage outside of react-native, I don't think it's the right fit for what I'm doing.