Update development notes

Author: icelam

DEVELOPMENT_NOTES.md

@@ -17,6 +17,19 @@ All the build files can be found in `/dist` folder.
 
 * `npm run build`
 
+### Debug ###
+* Chrome
+  1. Go to `chrome://extensions/` page
+  2. Enable development mode on upper right coner
+  3. Load unpack and select `/dist` folder
+
+* Firefox
+  1. Go to `about:debugging#/runtime/this-firefox` page
+  2. Choose `Load Temporary Add-on`
+  3. Select `manifest.json` inside `/dist` folder
+
+
 ### Pack Extension ###
-TBC
+* Chrome: Zip all content inside `/dist` folder after build, upload the zip file to webstore
+* Firefox: TBC