UWL: move the markers section into the marker element section

    mark-sequence {
        type:mark-sequence;
        name:"Sequence Marker";
        markers:m1;
    }
    @mark-sequence.m1 {
        type:marker;
        marker-type:annotations-count;
        marker-name:annotation_count;
        ">=1":good;
        "rest":Rest;
    }

    mark-sequence {
        type:mark-sequence;
        name:"Sequence Marker";
        marker {
            type:annotations-count;
            name:annotation_count;
            ">=1":good;
            "rest":Rest;
        }
    }