added asciitree as a core dependency
added asciitree as a core dependency

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