separate blog posts and blog post previews

[eristhea]

-------- MORE ----------- is awful and no fun to write around

[Southpaw1496]

We could put it in the front matter but that would mean repeating text. Why do you say that the system we have is bad?

[eristhea]

it makes writing an intro very difficult. if we could have two alternate intros, one in the preview and one in the real post, it would make writing less awkward