add tests for groupby

test/groupBy/test-groupby.sh

+lines_a=$(../../bin/groupBy -g 3-1 -o collapse -c 4 -i ../map/values3.bed | wc -l)
+lines_b=$(../../bin/groupBy -g 1-3 -o collapse -c 4 -i ../map/values3.bed | wc -l)
+lines_c=$(../../bin/groupBy -g 1,2,3 -o collapse -c 4 -i ../map/values3.bed | wc -l)
+lines_d=$(../../bin/groupBy -g 1-2,3 -o collapse -c 4 -i ../map/values3.bed | wc -l)
+
+check(){
+    if [ "$1" != "$2" ]; then
+        "fail groupby"
+    fi
+}
+
+check $lines_a $lines_b
+check $lines_a $lines_c
+check $lines_a $lines_d