How to customize the skeleton generators?

Hi Yii folks,

we want to customize the skeleton generator of YII to use YAML http://www.yaml.de/ as the default layout and CSS template. It seems, that the WebappCommand that creates the skeleton mainly copies some files from framework/cli/views into the new application and does some config. It would be easy to exchange the sources in this folder, but its not a good idea because its in the framework path. How would you extend YII to overload the default behavior and create custom skeletons ?

Kind regards,

Bergtroll