Fix filtering, detecting, reseting and ranking closes #135

[brownsarahm]

Ranking issues:

1. I can't rank until after detecting, which I don't think should be the case.
2. I set it to sum, distance rank and it added a mean view distance column.
3. when I change to max distance rank nothing happens.
4. after a few sucessful ranking and filter then i tried sum distance rank again and got the error below

raceback (most recent call last):
  File "/home/smb/Documents/code/detect_simpsons_paradox_dev/env/lib/python3.6/site-packages/flask/app.py", line 2463, in __call__
    return self.wsgi_app(environ, start_response)
  File "/home/smb/Documents/code/detect_simpsons_paradox_dev/env/lib/python3.6/site-packages/flask/app.py", line 2449, in wsgi_app
    response = self.handle_exception(e)
  File "/home/smb/Documents/code/detect_simpsons_paradox_dev/env/lib/python3.6/site-packages/flask/app.py", line 1866, in handle_exception
    reraise(exc_type, exc_value, tb)
  File "/home/smb/Documents/code/detect_simpsons_paradox_dev/env/lib/python3.6/site-packages/flask/_compat.py", line 39, in reraise
    raise value
  File "/home/smb/Documents/code/detect_simpsons_paradox_dev/env/lib/python3.6/site-packages/flask/app.py", line 2446, in wsgi_app
    response = self.full_dispatch_request()
  File "/home/smb/Documents/code/detect_simpsons_paradox_dev/env/lib/python3.6/site-packages/flask/app.py", line 1951, in full_dispatch_request
    rv = self.handle_user_exception(e)
  File "/home/smb/Documents/code/detect_simpsons_paradox_dev/env/lib/python3.6/site-packages/flask/app.py", line 1820, in handle_user_exception
    reraise(exc_type, exc_value, tb)
  File "/home/smb/Documents/code/detect_simpsons_paradox_dev/env/lib/python3.6/site-packages/flask/_compat.py", line 39, in reraise
    raise value
  File "/home/smb/Documents/code/detect_simpsons_paradox_dev/env/lib/python3.6/site-packages/flask/app.py", line 1949, in full_dispatch_request
    rv = self.dispatch_request()
  File "/home/smb/Documents/code/detect_simpsons_paradox_dev/env/lib/python3.6/site-packages/flask/app.py", line 1935, in dispatch_request
    return self.view_functions[rule.endpoint](**req.view_args)
  File "/home/smb/Documents/code/detect_simpsons_paradox_dev/env/lib/python3.6/site-packages/wiggum_app/controller.py", line 313, in main
    result_df = rank_result.to_json(orient='records'),
  File "/home/smb/Documents/code/detect_simpsons_paradox_dev/env/lib/python3.6/site-packages/pandas/core/generic.py", line 2425, in to_json
    index=index,
  File "/home/smb/Documents/code/detect_simpsons_paradox_dev/env/lib/python3.6/site-packages/pandas/io/json/_json.py", line 78, in to_json
    index=index,
  File "/home/smb/Documents/code/detect_simpsons_paradox_dev/env/lib/python3.6/site-packages/pandas/io/json/_json.py", line 122, in __init__
    self._format_axes()
  File "/home/smb/Documents/code/detect_simpsons_paradox_dev/env/lib/python3.6/site-packages/pandas/io/json/_json.py", line 211, in _format_axes
    "'{orient}'.".format(orient=self.orient)
ValueError: DataFrame columns must be unique for orient='records'.

detect issue: if threshold is too high that nothing is returned, everything goes blank, but no error announce. please add a popup.

thanks for tip on how to unselect. we should note that somewhere. Some select feilds work by clicking again.

FIlter issue:

1. reset should unselect the menu selections
2. if any filter settings are applied, they should be re-applied after detection. so, make a variable that's a part of wiggum app that's current_filters or something like that and hold those parameters there or have a binary variable filter that is false default, switches to true when filter btton pressed and to false when reset is pressed. or something similar.