Is Private on add/edit for other community content

[Paul Everitt]

Tres and Paul got Is Private working for folders (#361117).

We need it working for add/edit on files, wiki, blog entries, blog comments, and calendar events. We'll do this as part of M11.

Some wrinkles:

1) We can't have the sharing field appear in the validators if we are in the intranet side, since there is no such thing as isprivate over there. Thus, you'll see in karl.content.views.files.add_folder_view that, just after we make the form instance, we do a line where we call a helper to add the field if needed.

2) There's a place it gets added inside the "succeeded validation" then another place to add outside.

3) Unit tests will need a little love.

[Paul Everitt (paul-agendaless)]

*This* one is for Shane.

[Shane Hathaway (shane-hathawaymix)]

This is mostly finished, except:

- There is not yet an "is private" field for adding a comment.

- There are not enough tests for calendar events.

[Shane Hathaway (shane-hathawaymix)]

Committed in several revisions, the last of which is 2326.