Apply logging of arguments to modules (issue #122)

The ohai and facter modules use /usr/bin/logger to log the fact that
they have been invoked.  I added 'import os' to the ping module
so that it could have the same syslog statements as the other modules.
I separated the condensed:
    shlex.split(open(argfile, 'r').read())
into two separate statements similar to the other modules.

library/setup

@@ -31,6 +31,7 @@ import socket
 import struct
 import subprocess
 import traceback
+import syslog
 
 try:
     import json
@@ -295,6 +296,9 @@ except:
        (k,v) = opt.split("=")
        setup_options[k]=v   
 
+syslog.openlog('ansible-%s' % os.path.basename(__file__))
+syslog.syslog(syslog.LOG_NOTICE, 'Invoked with %s' % setup_options)
+
 ansible_file = os.path.expandvars(setup_options.get('metadata', DEFAULT_ANSIBLE_SETUP))
 ansible_dir = os.path.dirname(ansible_file)