added ability to input custom dropout map to quickflat
added ability to input custom dropout map to quickflat

smerdis/pycortex,gallantlab/pycortex,CVML/pycortex,CVML/pycortex,gallantlab/pycortex,smerdis/pycortex,CVML/pycortex,gallantlab/pycortex,CVML/pycortex,smerdis/pycortex,CVML/pycortex,gallantlab/pycortex,gallantlab/pycortex,smerdis/pycortex,smerdis/pycortex