include feature id in results where MultiPolygon

[andrewharvey]

👋 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 🚀

lookup.search where the Feature was a Polygon, returns the GeoJSON exactly as supplied including an id field, however that was broken when the Feature was a MultiPolygon.

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Here's what actually got changed 👏

where the indexed feature had an id, then include it is the search result.

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Here's how others can test the changes 👀

I first updated the unit test based on what should work, found it failed the test, then fixed the code, then found it passed.