Add support for boolean property table properties

[lilleyse]

We didn't add support for boolean properties in #573. It would look something like this:

• Allow boolean properties in MetadataUtil
• Add BOOLEAN to DataType, MdlInternalPropertyType, and MdlExternalPropertyType. Update template specializations in DataTypeUtil and anything else that switches based on DataType
• Add cesium_property_bool and cesium_internal_property_table_bool_lookup to cesium.mdl. cesium_property_bool can be modeled after cesium_property_int, cesium_internal_property_table_bool_lookup can be modelled after cesium_internal_property_table_int_lookup (but without has_no_data, no_data, and default_value, which aren't relevant for boolean properties).
• Update FabricMaterial
• Add cesium_property_bool to FabricUtil::isCesiumPropertyNode

I'm probably forgetting some areas, but this should be a good start.

Sample tileset: 3d-tiles-samples-boolean-in-property-table 2024-01-09.zip (same testing procedure as #614)