adding demo gif to README

Author: ganesshkumar

README.md

@@ -9,6 +9,9 @@ You can paste the copied Excel date from the clipboard by using either
 1. Hotkey - `Crtl/Cmd + Shift + V` or 
 2. Command Palette: `Ctrl/Cmd + P` > `Excel to Markdown` command
 
+![Obsidian Excel to Markdown Table](https://user-images.githubusercontent.com/2135089/151919147-8315155a-0972-4152-a8cc-70f835b6dece.gif)
+
+
 ## License
 [MIT](LICENSE)