Django support

[C0DK]

So it might be rather difficult to do, and i get the "i wrote it on an airplane" - but i like the idea of the code. However it doesn't really work with Django (i got a million deadcode things like my settings constants etc)

[asottile]

I'm not going to write django-specific knowledge into the tool but if you can come up with heuristics which apply more broadly then sure

there's also # dead: disable if you need to mark something as "yes this is actually used despite weirdness"

[asottile]

also note if you need to exclude specific files you an use `--exclude '/settings.py$' for instance