To allow you to set the allowBackup property of a cordova-android application
So I totally biffed on the fact that edit-config is now supported in config.xml as well as plugin.xml so you don't need the above plugin. All you need to do is add an edit-config section to your config.xml file like this:
<platform name="android">
<edit-config file="AndroidManifest.xml"
target="/manifest/application"
mode="merge">
<application android:allowBackup="false"/>
</edit-config>
</platform>
By default adding this plugin to your cordova-android project will set the android:allowBackup property in the <application/> tag to false.
cordova plugin add cordova-plugin-allow-backup
If you want to set the property to true use the BACKUP environment value.
cordova plugin add cordova-plugin-allow-backup --variable BACKUP=true