bump version to 0.4.20

Author: am1goo

README.md

@@ -8,7 +8,7 @@ Custom pipeline plugin about how to make work together Adobe Photoshop's files w
 
 #### Unity Plugin
 The latest version can be installed via [package manager](https://docs.unity3d.com/Manual/upm-ui-giturl.html) using following git URL: \
-`https://github.com/am1goo/unity-plugin-spritesheet-3000.git#0.4.14`
+`https://github.com/am1goo/unity-plugin-spritesheet-3000.git#0.4.20`
 
 ## Getting started
 #### Adobe Photoshop CC Extension

package.json

@@ -1,6 +1,6 @@
 {
     "name": "com.am1goo.spritesheet3000",
-    "version": "0.4.14",
+    "version": "0.4.20",
     "displayName": "Spritesheet 3000",
     "description": "Spritesheet 3000 Plugin for Unity",
     "dependencies": {