Remove some unused imports.
sync_posts: stop when you hit an existing post.

This makes things a bit faster.
Rename planet to all-posts.

This is a bit more descriptive if you aren't familiar with the piece of
software that we're not using.
Add landing page.
Work on deployability.

It's now possible to specify the path to the database, and we have a
proper wsgi app.
Add missing dependency on PyYAML.
Add MANIFEST.in