starting tagging

Still need to do view, submission and insta-rendering JavaScripts.

(Also, pulled setting the voting click-handlers into a function.)
Tag submission and insta-rendering
disallow tagging of other authors' posts
show posts with tag
nix setUpClass due to poor interaction with test db-cleaning behavior

See https://groups.google.com/forum/#!topic/django-developers/N0HEAD1ht8k
fix indentation to four spaces (!?!)

I'm kind of shocked that the interpreter let this happen at all (and
disappointed in Emacs, too). It looks like the interpreter actually
just tracks relative indentation (the "How does the compiler parse the
indentation?" section in
http://www.secnetix.de/olli/Python/block_indentation.hawk was
instructive on this point) rather than enforcing consistently
"globally", which totally makes sense in retrospect!
home link fixed
Merge branch 'tagging'
merging...I think...