Ajaxify the posts controller; refactor Post so you can get the URL data
out of the URL without constructing a post
Refactor Post so that you can get the URL data without creating a Post
blog_hostname should be base_hostname for consistency.  Made route work
around barely-documented implied constraint that segments are supposed
to not have dots in them (wtf?)
Don't need redirect to absolute URL
Submit form to the URL that will cause a redirect
Make route work with segment constraint that's barely documented