Tweaking tons 'o imports

A whole lotta import tweaks: 
* change `import settings` to `from django.conf import settings`
* change `from settings import ...` to `from kalite.settings import ...`, since this is how the `DJANGO_SETTINGS_MODULE` is set.
* move `utils` to `python_packages/fle_utils`, since (a) I thought I introduced a name conflict (turns out not...), and (b) we'll be moving this to a subtree shortly, from that location.

In the end, this didn't reduce the following problem:
![image](https://f.cloud.github.com/assets/4072455/2291939/1131c51c-a04c-11e3-95c8-19db2917c155.png)

Because in `manage.py`, `settings` is still referenced via `import settings` and not `import kalite.settings`.  I *could not* get the latter to work.  Any ideas out there?