add assassin walking animation

dist/shattered_sword_assets/spritesheets/Assassin.json

@@ -3,7 +3,7 @@
    "spriteSheetImage": "Assassin.png",
    "spriteWidth": 64,
    "spriteHeight": 64,
-    "columns": 13,
+   "columns": 16,
    "rows": 1,
    "durationType": "time",
    "animations": [
@@ -116,6 +116,28 @@
                "duration": 20
             }
          ]
+      },
+      {
+         "name": "WALK",
+         "repeat": true,
+         "frames": [
+            {
+               "index": 13,
+               "duration": 15
+            },
+            {
+               "index": 14,
+               "duration": 15
+            },
+            {
+               "index": 13,
+               "duration": 15
+            },
+            {
+               "index": 15,
+               "duration": 15
+            }
+         ]
       }
     ]
  }