improve

tasks/mergeBed.wdl

 	
 	command <<<
 
-		cat ${sep=" " mie_bed} > ${sample_name}.mie.bed
+		cat ${sep=" " mie_bed} | sort -k1,1 -k2,2n > ${sample_name}.mie.bed
 
-		cat ${sep=" " all_bed} > ${sample_name}.all.bed
+		cat ${sep=" " all_bed} | sort -k1,1 -k2,2n > ${sample_name}.all.bed
 
-		cat ${sep=" " info_bed} > ${sample_name}.info.bed
+		cat ${sep=" " info_bed} | sort -k1,1 -k2,2n > ${sample_name}.info.bed
 
 	>>>