Revert "No longer need to reference 'version_added' in docs for these, as this was quite a while ago."

This reverts commit ff0a41d4.

 - added terse syntax to modules.rst
 - added description of special variables to template module

  - .rst now supresses default if none is set (looks better in HTML)
  - .rst now handles empty options list
  - Fixed postgresql_user and mysql_user because YAML contained colons
  - docs for facter

Setup module no longer saves to disk, as templates are mostly useful in playbooks and this allows lots of simplifications
around file pathing and removes occasional permissions conflicts depending on how things are used.

still needs to daemonize.  Then, once done, playbook can be taught how to poll async within the
timing window.

CentOS5 has python 2.4 which doesn't have a built-in json
module