Update README of examples

examples/pane_grid/README.md

@@ -1,18 +1,28 @@
-## Counter
+## Pane grid
 
-The classic counter example explained in the [`README`](../../README.md).
+A grid of panes that can be split, resized, and reorganized.
+
+This example showcases the `PaneGrid` widget, which features:
+
+* Vertical and horizontal splits
+* Tracking of the last active pane
+* Mouse-based resizing
+* Drag and drop to reorganize panes
+* Hotkey support
+* Configurable modifier keys
+* API to perform actions programmatically (`split`, `swap`, `resize`, etc.)
 
 The __[`main`]__ file contains all the code of the example.
 
 <div align="center">
-  <a href="https://gfycat.com/fairdeadcatbird">
-    <img src="https://thumbs.gfycat.com/FairDeadCatbird-small.gif">
+  <a href="https://gfycat.com/mixedflatjellyfish">
+    <img src="https://thumbs.gfycat.com/MixedFlatJellyfish-small.gif">
   </a>
 </div>
 
 You can run it with `cargo run`:
 ```
-cargo run --package counter
+cargo run --package pane_grid
 ```
 
 [`main`]: src/main.rs