* Provides an abstraction for creating the JavaScriptEncoder used in SystemTextConfigurationEditorJsonSerializer.
* Generalised JSON serialization encoder factory to work for all System.Tex.Json serializers.
Added the serializer's name as a parameter to allow for different encodings per serializer if required.
* Fixed tests by removing use of obsolete constructors.
* Removed name parameter and used a generic type instead.
* Force system text json for IJSonSerializer
* Migrate ColorPickerValueConverter
* Move ColorPickerValueConverter
* Clean up ColorPickerValueConverter
* Remove obsoleted property editors
* Migrate FlexibleDropdownPropertyValueConverter to System.Text.Json
* Use IJsonSerializer instead and move the value converter to Core
* Migrate ImageCropperValueConverter to System.Text.Json
* Inject jsonserializer in test and obsolete old constructor
* Migrate JsonValueConverter to System.Text.Json
* Remove ContextualConfigurationEditorJsonSerializer
* Remove JsonNetSerializer
* Remove obsolete DeserializeSubset from JsonSerializer interface
* Fix FlexibleDropdownPropertyValueConverter
* Update test JSON to be actual valid json
* Update more test json
* Update time format to be valid
* Add JsonPropertyName to models
