Replace django-timezones w/ django-timezone-field

django-timezones does not support Python 3. django-timezone-field is
a revived fork that does.

For some unknown reason django-timezone-field's TimeZoneField does
not like positional arguments, so I changed to first argument to a
kwarg "verbose_name".

i18n all part

- forms for labels and helps
- views for success or warning messages
- apps and models verbose_names for admin

Signed-off-by: Hiroshi Miura <miurahr@linux.com>

python3 compatibility

- Things are suggested in python3 porting guide.
https://docs.djangoproject.com/en/1.8/topics/python3/

1. adding ```from django.utils.encoding import
python_2_unicode_compatible```

2. ``` __str__``` instead of ```__unicode__```
https://docs.djangoproject.com/en/1.8/topics/python3/#str-and-unicode-methods

3. Adding ```from __future__ import unicode_literals``` at the top
of your Python modules
https://docs.djangoproject.com/en/1.8/topics/python3/#unicode-literals

4. Removing the `u` prefix before unicode strings;
https://docs.djangoproject.com/en/1.8/topics/python3/#unicode-literals

- also closed #66

Signed-off-by: Hiroshi Miura <miurahr@linux.com>

Return unicode from _unicode_ methods

Import from PyCon improvement.

Author: Dan Poirier <dpoirier@caktusgroup.com>
Date: Mon Jul 8 15:55:33 2013 -0400

Return unicode from __unicode__ methods

Signed-off-by: Hiroshi Miura <miurahr@linux.com>

Remove migrations

These migrations were written for South. Now that we have Django 1.7,
we will just use Django migrations once we hit a 1.0 release.