fixes bug in duplicate url workflow

Previously when a duplicate url fragment was submitted, the user was
redirected to the comments page where they were provided a link to
resubmit the link. This resulting link did not include the original
url. This patch adds changes that preserve the url and title
throughout the submission workflow.

Fixes:
http://www.reddit.com/r/bugs/comments/1af12e/resubmitting_links_with_url_fragments_copies_a/