This commit adds support for fedora. It introduces a params namespace class to hold data differences between ubuntu and fedora. It also moves the xfs packages into their own class (swift::xfs)
Updates the defaults to ring creation to use replica of 3 and min part hours of 24. These are the defaults recommended by the swift documentation.
This commit adds test coverage for almost all swift classes and defines. It does not quite add 100% coverage (probably more like 85%)
