fixed handling of empty Project and ProjectCategory lists
fixed handling of empty Project and ProjectCategory lists

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