Reverted plugin.xml id to keep phonegap build compatibility

Author: jkasten2

plugin.xml

@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <plugin xmlns="http://www.phonegap.com/ns/plugins/1.0"
     xmlns:android="http://schemas.android.com/apk/res/android"
-    id="onesignal-cordova-plugin"
+    id="com.onesignal.plugins.onesignal"
     version="1.7.1">
 
   <name>OneSignal Push Notifications</name>