Add tumblr duplicate support
Add tumblr duplicate support

This addresses reload of first item link bug.
This uses duplicate functionality to track "source" links in tumblr,
essentially tracking cross-posts.
Rename photo.commentsLink to photo.comments

Signed-off-by: Nathaniel Clark <865dbb93f30fb195f09da9caf5665329e84a4b97@misrule.us>

utopiabound/redditp,utopiabound/redditp