Make sharing match parent items

When publishing from VSW copies of portal items are created for each items referenced. These all have sharing set to owner only and no groups as default. 

As an example I can make a new print template; share with everyone; then add it to my VSW app. After publishing I will have new items in the following state
Print Template - Everyone
Print Template (Test) - Owner
Print Template (Prod) - Owner

Meaning that unless I remember to update every portal item created my public apps will start prompting users to sign-in. 

While thankfully these permissions need only be updated once; publishing should also copy permissions when publishing.