Fix additional_dir serving

[Thingee]

Removing undefined cases, and moving a referenced variable after being
defined. Was getting 500 errors on serving because of several issues fixed in this pull request.

Traceback (most recent call last):
  File "/usr/local/lib/python2.7/dist-packages/werkzeug/serving.py", line 193, in run_wsgi
    execute(self.server.app)
  File "/usr/local/lib/python2.7/dist-packages/werkzeug/serving.py", line 181, in execute
    application_iter = app(environ, start_response)
  File "/usr/local/lib/python2.7/dist-packages/flask/app.py", line 1836, in __call__
    return self.wsgi_app(environ, start_response)
  File "/usr/local/lib/python2.7/dist-packages/flask_socketio/__init__.py", line 37, in __call__
    start_response)
  File "/usr/local/lib/python2.7/dist-packages/engineio/middleware.py", line 49, in __call__
    return self.wsgi_app(environ, start_response)
  File "/usr/local/lib/python2.7/dist-packages/flask/app.py", line 1820, in wsgi_app
    response = self.make_response(self.handle_exception(e))
  File "/usr/local/lib/python2.7/dist-packages/flask/app.py", line 1410, in handle_exception
    return handler(e)
  File "/usr/local/lib/python2.7/dist-packages/instant_rst/server.py", line 114, in server_error
    console.log(e)
NameError: global name 'console' is not defined

and then later

local variable 'additional_dir' referenced before assignment 

[gu-fan]

well... sorry..