add heatmap

tasks/export.wdl

     String disk_size
 
     command <<<
-        # mkdir -p /cromwell_root/tmp/cnvkit
         cp -r ${sep=" " results} .
-        # cd /cromwell_root/tmp/cnvkit
-        # this version app just provides seg
+        # seg
         cnvkit.py export seg *.cns -o ${sample_id}.seg
+        # heatmap
+        cnvkit.py heatmap *.cns -o ${sample_id}.heatmap
     >>>
    
     runtime { 
 
     output {
         File seg = "${sample_id}.seg"
+        File heatmap = "${sample_id}.heatmap"
     }
 }