Update player.py

Removed the following lines from the @OOC command to prevent the player is leaving the game message from appearing twice:

save location as if we were disconnecting from the game entirely.
        if old_char.location:
            old_char.location.msg_contents("%s has left the game." % old_char.key, exclude=[old_char])
Update objects.py

Removed the following line from at_pre_puppet, because it is repeated in at_post_puppet and results in the message "%s has entered the game" appearing twice.

self.location.msg_contents("%s has entered the game." % self.name, exclude=[self])
Update objects.py
Update requirements.txt

Updated South requirement from >=0.8 to >=0.8.4 to correspond with changes to the Getting Started page due to reported issues with South 0.8.2 and 0.8.3.
Merge pull request #470 from delizin/master

Resolution to issue #469: Messages "Player has enter the game" and "Player has left the game" repeated twice.