[development] Time to remove poll module from core

[Jeff Eaton]

> I don't think demoting polls to a second class data type as 
> an answer; a 
> poll should be a node, but we need our blogs and forums to be able to 
> accept more content types than just 'blog' or 'forum'.

I'm with Earl on this one. Blogs are not a *content type* even though we
treat them that way in blog.module. They're a container, and (in most
cases) a presentation style. "Blogs" should be able to accept weblink
nodes, images, polls, journal entries, and so on.

--Jeff