[app] Remove config.xml
[app] Remove config.xml

For now, this is only supported by PhoneGap Build.
Including it in the Apache Cordova Hello World app,
before its supported, may be confusing and misleading.

agilemation/cordova-app-hello-world,hypery2k/cordova-demo-app,apache/cordova-app-hello-world,stgnet/cordova-app-hello-world,mwbrooks/incubator-cordova-app-hello-world,mikekreeki/cordova-geo-test,stgnet/cordova-app-hello-world,jsoref/cordova-app-hello-world,agilemation/cordova-app-hello-world,hypery2k/cordova-demo-app,hypery2k/cordova-demo-app,jensaug/cordova-app-hello-world,hypery2k/cordova-demo-app,apache/cordova-app-hello-world,jsoref/cordova-app-hello-world,jensaug/cordova-app-hello-world