Add Simple WKT Shape Parser [LUCENE-8538]

Similar to `SimpleGeoJSONPolygonParser` for creating `Polygon` objects from GeoJSON, it would be helpful to have a `SimpleWKTParser` for creating lucene geometries from WKT. Not only is this useful for simple tests, but also helps for benchmarking from real world data (e.g., PlanetOSM).

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Migrated from [LUCENE-8538](https://issues.apache.org/jira/browse/LUCENE-8538) by Nick Knize (@nknize), updated Oct 24 2018
Attachments: [LUCENE-8538.patch](https://apache.github.io/lucene-jira-archive/attachments/LUCENE-8538/LUCENE-8538.patch)

Start by reading the existing SimpleGeoJSONPolygonParser mentioned in the issue and the attached LUCENE-8538.patch. Determine the WKT shapes and Lucene geometry objects the SimpleWKTParser must support, then verify that parsed WKT can create Polygon objects for simple tests and real-world benchmarking data such as PlanetOSM.

Written by the indexing model from the issue text.