Prints time before and after sleep() with approximately millisecond accuracy.
Displays seconds and microseconds, both before and after sleep().
This demonstrates wrappers around wrappers.  The plugin ../sleep1 wraps
  this plugin sleep2, which wraps sleep() in libc.so

To demonstrate, do:  make check    [Checkpoints every 5 seconds]
After killing it, try:  ./dmtcp_restart_script.sh
... and 'pkill -9 dmtcp' to later kill it.
