Remove /etc/hosts entry for puppet

Prior to this commit, an entry for puppet was added to 127.0.0.1
This interferes with the ability of the students to be able to use the
defaults in the puppet enterprise installer in the new fundamentals
class (17436). This is a fix for ticket 13330 in redmine.
Merge pull request #52 from acidprime/fundamentals/tickets/13330

#(13330) Remove /etc/hosts entry for puppet