Shape ingestion support

[lokkju]

👋 I have added the ability to optionally ingest shapes

actually returning shape geometry from elasticsearch depends on other changes in schema and api; those pull requests are also being created, and the entire stack can be seen here: https://github.com/lokkju/pelias-us-shape-autocomplete

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Here's the reason for this change 🚀

admin region boundary display has been a long desired feature, but it should be optional as it increases index size. This changeset enables the optional ingestion of boundaries from whosonfirst data into the pelias-schema shape field.

• requires adding support for optionally customizing the document model from pelias.json schema#493 to actually store/return the shapes from elasticsearch

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Here's what actually got changed 👏

• added an importShapes option to the config, defaulting to false
• changed the extractFields signature to accept a wofConfig object
• added the extraction of the geometry field to the extractFields module
• in the peliasDocGenerators module, set the doc shape if a geometry field exists
• added and fixed up existing tests

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Here's how others can test the changes 👀

Unit tests were added, and the full stack of changesets can be tried from the above repository.