CB-7118 iOS: add target-device and MinimumOSVersion support to config.xml

https://issues.apache.org/jira/browse/CB-7118
Looks like your changes to xcode module were accepted and also released as version `0.6.7`. I think it would be best to put in the new `updateBuildProperty` and get this merged, along with an update to the `xcode` version in the dependency list.