worlddump: add empty newline after every command output

It makes it a bit easier to read the output since each new command is
now visually separated from the output of the previous one.

Change-Id: If441c61bb6f13f85f771dd31609b10d3dd1ee93c
diff --git a/tools/worlddump.py b/tools/worlddump.py
index 9d2b082..d67f226 100755
--- a/tools/worlddump.py
+++ b/tools/worlddump.py
@@ -56,6 +56,7 @@
     print
     try:
         subprocess.check_call(cmd, shell=True)
+        print
     except subprocess.CalledProcessError:
         print "*** Failed to run: %s" % cmd