revise readme

tasks/cat_rename.wdl

 task cat_rename {
-	String raw_name
+	File raw_name
 	String new_name
 	String cluster_config
 
 	}
 
 	output {
-		new_name_fq_1 = "${new_name}_1.fq.gz"
-		new_name_fq_2 = "${new_name}_2.fq.gz"
+		File new_name_fq_1 = "${new_name}_1.fq.gz"
+		File new_name_fq_2 = "${new_name}_2.fq.gz"
 	}
 }

workflow.wdl

 	String docker
 	String cluster_config
 	String disk_size
-	String raw_name
+	File raw_name
 	String new_name
 
 	call cat_rename.cat_rename as cat_rename {