Fixed pidfile open in write mode.

bin/cc-node

@@ -36,7 +36,7 @@ if not isfile(options.config):
 
 # take care of pid file if daemon
 if options.daemonize:
-    pidfile = open(options.pidfile)
+    pidfile = open(options.pidfile, 'w')
     files_preserve = [pidfile]
 else:
     files_preserve = None