feat: Update preview

[arnesetzer]

👋 I did some awesome work for the Pelias project and would love for everyone to have a look at it and provide feedback.

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Here's the reason for this change 🚀

As discussed in #373 here is updated version with https://github.com/geocodeearth/autocomplete-element instead of nextzen-leaflet. Due to laziness the url (localhost:4000) is hardcoded in the bundle.js. We could link the api in the docker-compose.yml which would allow us to use the container name instead of ip but wont solve the problem with the port. But since this is only nice2have I don't see it as this big of a problem.

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Here's what actually got changed 👏

• Update the leaflet packages to the latest version
• Fix the stamen tile url
• replace nextzen-leaflet witjk autocomplete-element

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Here's how others can test the changes 👀

Fire up any project with existing data, go to "localhost:3000" and search something.

Closes #373

[orangejulius]

I forgot to reply to this earlier, but it's very nice. Maybe we wait until after #386 is merged so that this diff is much smaller and simpler?