Update readme with the new screenshot

Author: Xpirix

img/homepage.webp

@@ -1 +1 @@
-2.0.2
+3.0.0

qgis-app/.version

@@ -1,13 +1,17 @@
 # Introduction
 
-![image](https://user-images.githubusercontent.com/178003/91536115-2356ec80-e90c-11ea-971b-f23ac72d3aea.png)
+![image](./img/homepage.webp)
 
 This directory contains the source code for the plugin repository server used by
 the QGIS project.
 
 This software is open source and licensed under GNU General Public License v2.0.
 For licensing information, please read the COPYING file included in this directory.
 
+## Important Note
+
+***This repository is dedicated solely to the QGIS Plugins Website (plugins.qgis.org). For issues related to specific plugins or other concerns, please use the respective bug tracker.***
+
 ## Installation
 
 For setup, installation and backup notes, please read [INSTALL](INSTALL.md) included in this directory.