Add verbose and normal formatters ; create the default log directory

Add `verbose` and `normal` formatters:

```
$ python manage.py runserver
Traceback (most recent call last):
  File "manage.py", line 10, in <module>
    execute_from_command_line(sys.argv)
  File "/usr/local/lib/python2.7/dist-packages/django/core/management/__init__.py", line 453, in execute_from_command_line
    utility.execute()
  File "/usr/local/lib/python2.7/dist-packages/django/core/management/__init__.py", line 392, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File "/usr/local/lib/python2.7/dist-packages/django/core/management/__init__.py", line 263, in fetch_command
    app_name = get_commands()[subcommand]
  File "/usr/local/lib/python2.7/dist-packages/django/core/management/__init__.py", line 109, in get_commands
    apps = settings.INSTALLED_APPS
  File "/usr/local/lib/python2.7/dist-packages/django/conf/__init__.py", line 53, in __getattr__
    self._setup(name)
  File "/usr/local/lib/python2.7/dist-packages/django/conf/__init__.py", line 49, in _setup
    self._configure_logging()
  File "/usr/local/lib/python2.7/dist-packages/django/conf/__init__.py", line 84, in _configure_logging
    logging_config_func(self.LOGGING)
  File "/usr/lib/python2.7/logging/config.py", line 797, in dictConfig
    dictConfigClass(config).configure()
  File "/usr/lib/python2.7/logging/config.py", line 579, in configure
    '%r: %s' % (name, e))
ValueError: Unable to configure handler 'normal': Unable to set formatter 'verbose': 'verbose'
```
Create the default log directory:
```
python manage.py default
Traceback (most recent call last):
  File "manage.py", line 10, in <module>
    execute_from_command_line(sys.argv)
  File "/usr/local/lib/python2.7/dist-packages/django/core/management/__init__.py", line 453, in execute_from_command_line
    utility.execute()
  File "/usr/local/lib/python2.7/dist-packages/django/core/management/__init__.py", line 392, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File "/usr/local/lib/python2.7/dist-packages/django/core/management/__init__.py", line 263, in fetch_command
    app_name = get_commands()[subcommand]
  File "/usr/local/lib/python2.7/dist-packages/django/core/management/__init__.py", line 109, in get_commands
    apps = settings.INSTALLED_APPS
  File "/usr/local/lib/python2.7/dist-packages/django/conf/__init__.py", line 53, in __getattr__
    self._setup(name)
  File "/usr/local/lib/python2.7/dist-packages/django/conf/__init__.py", line 49, in _setup
    self._configure_logging()
  File "/usr/local/lib/python2.7/dist-packages/django/conf/__init__.py", line 84, in _configure_logging
    logging_config_func(self.LOGGING)
  File "/usr/lib/python2.7/logging/config.py", line 797, in dictConfig
    dictConfigClass(config).configure()
  File "/usr/lib/python2.7/logging/config.py", line 579, in configure
    '%r: %s' % (name, e))
ValueError: Unable to configure handler 'normal': [Errno 2] No such file or directory: '/home/yoyo/projects/yeti/yeti/log/yeti.log'
```