Add screenshot to README

Author: ogxd

Demo/screenshot.gif

@@ -1,14 +1,16 @@
 # UnityPacker
 
-UnityPacker is a collection of a library and small command line tools that can create, unpack and inspect `UnityPackage` files without a Unity installation. It is great for automated builds of Unity tools.
+UnityPacker is a collection of a library and small command line tools that can create, unpack and inspect `UnityPackage` files without a Unity installation. It is great for automated builds of Unity tools.    
+
+![Screenshot](https://raw.githubusercontent.com/ogxd/unity-packer/master/Demo/screenshot.gif)
 
 *Tested on Unity 2018.3 and 2019.1.0f2*
 
-> This repository was forked from [FatihBAKIR/UnityPacker](https://github.com/FatihBAKIR/UnityPacker) and refactored to fix path issues, usage and compatibility.
+> This repository was initially forked from [FatihBAKIR/UnityPacker](https://github.com/FatihBAKIR/UnityPacker) and then heavily refactored.
 
 ## How to create .unitypackage
 
-    ./UnityPack mode=pack folder="" package="Samples" root="Assets/Plugins/Product/Samples" ignore="(Plugins\\.*|unitypackage|exe|exe|cmd)$"
+    ./UnityPacker mode=pack folder="." package="Samples" root="Assets/Plugins/Product/Samples" ignore="(Plugins\\.*|unitypackage|exe|exe|cmd)$"
 
 This example will produce a `Samples.unitypackage` from the contents current directory recursively in the current directory.
 
@@ -18,6 +20,6 @@ This example will produce a `Samples.unitypackage` from the contents current dir
 
 ## How to extract .unitypackage
 
-    .//UnityPacker mode=unpack package="Samples.unitypackage" destination="."
+    ./UnityPacker mode=unpack package="Samples.unitypackage" destination="."
 
 This example will unpack the `Samples.unitypackage` to the working directory, with proper directory structure.