Heroku Fork should allow exclusion of add-ons

[YuniSocial]

Should be able to avoid this :

$ heroku fork --from sourceapp --to targetapp
Forking sourceapp... done. Forked to targetapp
Setting buildpacks... done
Adding zerigo_dns:free to targetapp as ZERIGO_DNS... !
▸ Application error.

There was an error forking to targetapp.

In order to avoid being charged for any resources on targetapp, it is being destroyed...
Destroying app targetapp... done