Merge branch '4.0' into 4.1-beta

# Conflicts:
#	spine-csharp/src/Attachments/IHasTextureRegion.cs.meta
#	spine-ts/package-lock.json
#	spine-ts/package.json
#	spine-ts/spine-canvas/package.json
#	spine-ts/spine-core/package.json
#	spine-ts/spine-player/package.json
#	spine-ts/spine-threejs/package.json
#	spine-ts/spine-webgl/package.json

spine-ts/spine-core/src/SkeletonBinary.ts

@@ -1058,7 +1058,7 @@ export class BinaryInput {
 		let chars = "";
 		let charCount = 0;
 		for (let i = 0; i < byteCount;) {
-			let b = this.readByte();
+			let b = this.readUnsignedByte();
 			switch (b >> 4) {
 				case 12:
 				case 13:

spine-unity/Modules/com.esotericsoftware.spine.timeline/Editor/SpineAnimationStateGraphicTrackInspector.cs

@@ -34,7 +34,7 @@ using UnityEngine;
 using UnityEngine.Timeline;
 
 namespace Spine.Unity.Editor {
-
+#if UNITY_2019_1_OR_NEWER
 	[CustomTimelineEditor(typeof(SpineAnimationStateGraphicTrack))]
 	[CanEditMultipleObjects]
 	public class SpineAnimationStateGraphicTrackInspector : TrackEditor {
@@ -46,4 +46,22 @@ namespace Spine.Unity.Editor {
 			return options;
 		}
 	}
+#else
+	[CustomEditor(typeof(SpineAnimationStateGraphicTrack))]
+	[CanEditMultipleObjects]
+	public class SpineAnimationStateGraphicTrackInspector : UnityEditor.Editor {
+
+		protected SerializedProperty trackIndexProperty = null;
+
+		public void OnEnable () {
+			trackIndexProperty = serializedObject.FindProperty("trackIndex");
+		}
+
+		public override void OnInspectorGUI () {
+			serializedObject.Update();
+			EditorGUILayout.PropertyField(trackIndexProperty);
+			serializedObject.ApplyModifiedProperties();
+		}
+	}
+#endif
 }

spine-unity/Modules/com.esotericsoftware.spine.timeline/Editor/SpineAnimationStateTrackInspector.cs

@@ -34,6 +34,7 @@ using UnityEngine;
 using UnityEngine.Timeline;
 
 namespace Spine.Unity.Editor {
+#if UNITY_2019_1_OR_NEWER
 	[CustomTimelineEditor(typeof(SpineAnimationStateTrack))]
 	[CanEditMultipleObjects]
 	public class SpineAnimationStateTrackInspector : TrackEditor {
@@ -45,4 +46,22 @@ namespace Spine.Unity.Editor {
 			return options;
 		}
 	}
+#else
+	[CustomEditor(typeof(SpineAnimationStateTrack))]
+	[CanEditMultipleObjects]
+	public class SpineAnimationStateTrackInspector : UnityEditor.Editor {
+
+		protected SerializedProperty trackIndexProperty = null;
+
+		public void OnEnable () {
+			trackIndexProperty = serializedObject.FindProperty("trackIndex");
+		}
+
+		public override void OnInspectorGUI () {
+			serializedObject.Update();
+			EditorGUILayout.PropertyField(trackIndexProperty);
+			serializedObject.ApplyModifiedProperties();
+		}
+	}
+#endif
 }

spine-unity/Modules/com.esotericsoftware.spine.timeline/Editor/SpineSkeletonFlipTrackInspector.cs

@@ -34,6 +34,7 @@ using UnityEngine;
 using UnityEngine.Timeline;
 
 namespace Spine.Unity.Editor {
+#if UNITY_2019_1_OR_NEWER
 	[CustomTimelineEditor(typeof(SpineSkeletonFlipTrack))]
 	[CanEditMultipleObjects]
 	public class SpineSkeletonFlipTrackInspector : TrackEditor {
@@ -45,4 +46,5 @@ namespace Spine.Unity.Editor {
 			return options;
 		}
 	}
+#endif
 }