Throttle keyboard sort

Author: Brian Ryu

src/SortableContainer/index.js

@@ -1005,6 +1005,17 @@ export default function sortableContainer(
     };
 
     keyMove = (shift) => {
+      const {transitionDuration} = this.props;
+
+      if (this.keyMoving) {
+        return;
+      } else {
+        this.keyMoveInterval = setTimeout(() => {
+          this.keyMoving = false;
+        }, transitionDuration);
+        this.keyMoving = true;
+      }
+
       const {
         activeKeyLift: {index, collection},
       } = this.manager;