Prior to this commit, if you attempted to use the module to
manage postgres on any OS other than Redhat/Debian, there
was an explicit check for that, and a call to `fail`.
In reality, the OS family is only used to build up defaults
for various path and package names, which are all exposed
as parameters. If the user is willing to explicitly pass
in all of those parameters, there's no reason we should
fail based on OS family.
This commit adds checks to the 'default' osfamily case
such that we now only fail if they're on a non-Redhat-or-Debian
system *and* they haven't explicitly passed in values for
all of the required parameters.
Thanks to some tricks I learned from Nan Liu and Dan Bode, I was
able to figure out a way to move all of the new version-related stuff
back into the params class, and clean up some of the if/_real stuff.
Basic tests for centos6 + pg 9.2 are passing.
Nan showed me a trick that will let us keep all of that param stuff
inside of params.pp, make it a parameterized class, and still support
the ability for users to specify a custom (non-system-default) pg
version. This commit takes the first step towards that pattern by
consolidating platform.pp and params.pp. (Everything old is new again!)
