Update to config path within plugin.xml

Excellent work on this plugin. Thank you for your work.

The config file path is set as <config-file target="config.xml" parent="/*">.
This throws an error "class not found" and the config file is not updated correctly on build.

The original source it is set within the res/xml/ folders. <config-file target="res/xml/config.xml" parent="/*">
It works fine with this path.