fixed gff output

    path bigwig

    output:

    path('*.{txt,xml,bed,bigWig,fa,gtf}', includeInputs:true)

    path('*.{txt,xml,bed,bigWig,fa,gtf,gff}', includeInputs:true)

    path  "versions.yml"                , emit: versions

    when:

    """

    echo "$output" > exp_files.txt

    find -L * -iname "*.gtf" -exec echo -e {}"\\t0,48,73" \\; > gtf.igv.txt

    find -L * -iname "*.gff" -exec echo -e {}"\\t0,48,73" \\; > gff.igv.txt

    cat *.txt > igv_files.txt

    igv_files_to_session.py igv_session.xml igv_files.txt $genome --path_prefix './'