Removed the call to waitpid in pfork

The call to waitpid, on OSX (tested on 10.7 and 10.9) block for _one_
    of the calls for about 2sec. This is usually on one of the first 3
fork
    IDs.

    As the previous reading from the pipe provides for the necessary
    synchronization the call to waitpid is redundant. Uncommenting for
now.