Make subs private

Moved unless statements over to private() from stdlib.

Embedding private()s into sub-classes as an attempt to prevent people from instantiating sub-classes with include/require when they should probably include/require base implementation class and perhaps set up dependencies to the base class or perhaps the subclass.

Ex

```puppet
# No!
class foo::service {
  require ::bar::service
}

# Better!
class foo::service {
  include ::bar
  Class[::bar::service] -> Class[::foo::service]
}
```