[chef] Clean up file_cache automatically when using chef-solo

[howard chen < >]

We are using chef-solo and the the file_cache get larger and larger and files won't be deleted.

It is possible to tell chef that everytime when chef-solo is run, it remove all the files inside the file_cache automatically?

(Definitely I can rm myself, but I am looking for cross platform way or preferred way to do it)

Thanks.