fitter can now run in plot silent mode.

In fitter self._settings['autoplot'] is a list of two elements.  This is... always True.  To check for plotting fitter now looks at self._settings['autoplot'][0] to see if plots should be drawn.

@jaxankey , let me know if I am missing something.  This is not a great fix but it certainly gets the job done.  I didn't look into the details of why self._settings['autoplot'] is a list of two elements.  I probably should have just spent the time to fix this.