Update CHANGES, add CesiumJsonReader to README

CHANGES.md

@@ -2,11 +2,27 @@
 
 ### v0.1.1 - ?
 
-- Gave glTFs created from quantized-mesh terrain tiles a more sensible material with a `metallicFactor` of 0.0 and a `roughnessFactor` of 1.0. Previously the default glTF material was used, which has a `metallicFactor` of 1.0, leading to an undesirable appearance.
-- Reported zero-length images as non-errors as `BingMapsRasterOverlay` purposely requests that the Bing servers return a zero-length image for non-existent tiles.
-- Added diagnostic details to error messages for invalid glTF inputs
+##### Breaking Changes :mega:
+
+- Moved `JsonValue` from the `CesiumGltf` library to the `CesiumUtility` library and changes some of its methods.
+- Renamed `CesiumGltf::Reader` to `CesiumGltf::GltfReader`.
+- Made the `readModel` and `readImage` methods on `GltfReader` instance methods instead of static methods.
+
+
+##### Additions :tada:
+
+- Added `CesiumJsonReader` library.
+- Added diagnostic details to error messages for invalid glTF inputs.
 - Added an `Axis` enum and `AxisTransforms` class for coordinate system transforms
 - Added support for the legacy `gltfUpVector` string property in the `asset` part of tilesets. The up vector is read and passed as an `Axis` in the `extras["gltfUpVector"]` property, so that receivers may rotate the glTF model's up-vector to match the Z-up convention of 3D Tiles.
+- Unknown glTF extensions are now deserialized as a `JsonValue`. Previously, they were ignored.
+- Added the ability to register glTF extensions for deserialization using `GltReader::registerExtension`.
+- Added `GltfReader::setExtensionState`, which can be used to request that an extension not be deserialized or that it be deserialized as a `JsonValue` even though a statically-typed class is available for the extension.
+
+##### Fixes :wrench:
+
+- Gave glTFs created from quantized-mesh terrain tiles a more sensible material with a `metallicFactor` of 0.0 and a `roughnessFactor` of 1.0. Previously the default glTF material was used, which has a `metallicFactor` of 1.0, leading to an undesirable appearance.
+- Reported zero-length images as non-errors as `BingMapsRasterOverlay` purposely requests that the Bing servers return a zero-length image for non-existent tiles.
 - 3D Tiles geometric error is now scaled by the tile's transform.
 
 ### v0.1.0 - 2021-03-30

README.md

@@ -27,6 +27,7 @@ Currently Cesium Native is used to develop [Cesium for Unreal](https://github.co
 | **CesiumGltfReader** | glTF deserialization / decoding, including glTF extension support (`KHR_draco_mesh_compression` etc). |
 | **CesiumGltfWriter** | glTF serialization / encoding, including glTF extension support. |
 | **CesiumIonClient** | Functions to access [Cesium ion](https://cesium.com/cesium-ion/) accounts and 3D tilesets using ion's REST API. |
+| **CesiumJsonReader** | Reads JSON from a buffer into statically-typed classes. |
 | **CesiumUtility** | Utility functions for JSON parsing, URI processing, etc. |