* Private members may not satisfy protocol requirements, ever.
...because by construction they can be invoked from outside of the
type.
Finishing up SE-0025 ('private' and 'fileprivate').
* Update docs and mark SE-0025 ('private' and 'fileprivate') as done!
There's still improvements we can make (see 508e825f), but the feature
is in place and should be working correctly.
- Add a note about protocol extension members being used for conformances.
- Phrase in present tense.
- Remove references to "Swift 1.0".
- Replace "accessibility" with "access level". "Accessibility" has another
meaning for app developers, so we avoid the term now in the compiler.
- 'required' and 'final' are now modifiers.
- 'internal' declarations don't show up in generated headers for frameworks.
- Remove the section on unit tests. We now have @testable.
- Remove the section on transparent functions, which isn't fully designed.
Swift SVN r31858
