Update README to include TWKB

README.md

@@ -104,6 +104,7 @@ Simple features supports the following external geometry representation formats:
 | WKT     | `POLYGON((0 0,0 1,1 1,1 0,0 0))`                                     | [Well Known Text](https://en.wikipedia.org/wiki/Well-known_text_representation_of_geometry) is a human readable format for storing geometries. It's often the lowest common denominator geometry format, and is useful for integration with other GIS applications.                                                                                                |
 | WKB     | `<binary>`                                                           | [Well Known Binary](https://en.wikipedia.org/wiki/Well-known_text_representation_of_geometry#Well-known_binary) is a machine readable format that is efficient for computers to use (both from a processing and storage space perspective). WKB is a good choice for transferring geometries to and from PostGIS and other databases that support geometric types. |
 | GeoJSON | `{"type":"Polygon","coordinates":[[[0,0],[0,1],[1,1],[1,0],[0,0]]]}` | [GeoJSON](https://en.wikipedia.org/wiki/GeoJSON) represents geometries in a similar way to WKB, but is based on the JSON format. This makes it ideal to use with web APIs or other situations where JSON would normally be used.                                                                                                                                   |
+| TWKB    | `<binary>`                                                           | [Tiny Well Known Binary](https://github.com/TWKB/Specification) is a multi-purpose compressed binary format for serialising vector geometries into a stream of bytes. It emphasises minimising the size of the serialised representation. It's a good choice when space is at a premium (e.g. for storage within a web token).                                     |
 
 ### Geometry Algorithms