Let pod list grep without external pipe

pod

@@ -88,11 +88,19 @@ case "$CMD" in
         exit
         ;;
     list)
-        find_unlistened --in=here
+        if [ $# -lt 1 ] ; then
+            find_unlistened --in=here
+        else
+            find_unlistened --in=here | grep $@
+        fi
         exit
         ;;
     list-all)
-        find_unlistened
+        if [ $# -lt 1 ] ; then
+            find_unlistened
+        else
+            find_unlistened | grep $@
+        fi
         exit
         ;;
     play)