added back Pillow since it's needed for ImageField
added back Pillow since it's needed for ImageField

ssadedin/seqr,macarthur-lab/xbrowse,ssadedin/seqr,ssadedin/seqr,macarthur-lab/seqr,macarthur-lab/xbrowse,macarthur-lab/seqr,macarthur-lab/seqr,macarthur-lab/xbrowse,macarthur-lab/seqr,macarthur-lab/xbrowse,ssadedin/seqr,macarthur-lab/xbrowse,ssadedin/seqr,macarthur-lab/xbrowse,macarthur-lab/seqr