Docs Only stories do not work in SB7 with the v6 store.

[tmeasday]

It seems like the current implementation doesn't support them. The issues are:

• We don't handle docs only stories in StoryStoreFacade.addStoriesFromExports() currently. We should add a docs entry to the internal story index for each docs only story.

• SET_STORIES filters out docs entries, in order to be back-compat (I'm not sure if we want to change this).

• So there would be no way to pass the docs only story over the SET_STORIES event, unless we passed it as a story.

Perhaps this means we should pass them over as story entries rather than docs entries. This breaks the model in other places though (for instance we don't do this for docs page entries in v6, instead we recalculate the entries on the manager side, which is a bit crappy). We might want to rethink that though.

[tmeasday]

We fixed this.