Change print statements to work in python3

This is part of a series of changes to introduce Python3 support.

Change-Id: I373be5de7141aa127d7debdbce1df39148dbec32
diff --git a/subcmds/status.py b/subcmds/status.py
index 7611621..4056227 100644
--- a/subcmds/status.py
+++ b/subcmds/status.py
@@ -129,4 +129,4 @@
         output.dump(sys.stdout)
         output.close()
     if len(all_projects) == counter.next():
-      print 'nothing to commit (working directory clean)'
+      print('nothing to commit (working directory clean)')