add shader graph examples

add particle system examples (WIP)

Simulation/Assets/UnityTechnologies/ParticlePack/Shared/Ramps/Runtime/RampAsset.cs

@@ -0,0 +1,13 @@
+using System.Collections;
+using System.Collections.Generic;
+using UnityEngine;
+
+
+    [CreateAssetMenu]
+    public class RampAsset : ScriptableObject
+    {
+        public Gradient gradient = new Gradient();
+        public int size = 16;
+        public bool up = false;
+        public bool overwriteExisting = true;
+    }