Post Markdown assignment

I commented out the markdown method in the application helper file.  I
then created a private method render_as_markdown in the post.rb file,
and created two new methods in this file for title and body.  I changed
the post/show file to work with these two methods.  I added, committed
and pushed these changes from this branch.  Submitted a pull request,
and am not deleting or merging this branch.  Will checkout master, and
create a new branch to do the  next checkpoint.