Remove unused layouts.

Remove unused layouts that were originally for displaying a listing of
unpublished posts when signed in.
Abstract the pager into a partial.

Abstract the pager into a partial that can be used in the blog post
index and the abridged blog post index which displayed unpublished
posts.
Remove unused haml views from blog_posts.
Improve naming consistency for unpublished posts.

Improve the naming consistency for unpublished blog posts by renaming
the abridged_blog_post partial and abridged_index view to
unpublished_blog_post and unpublished_index.  These views are really
used to display unpublished posts and the names should reflect that to
reduce confusion.
Make the content box wider in blog post form.

Make the content box wider in the blog post form partial.  This is done
by setting the class on the text area to a valid bootstrap 3 class which
spans a desired number of "columns" in the bootstrap grid.