CHEF-4885: Chef::ReservedNames::Win32::Version has invalid methods

Currently this class has a method named "windows_8.1?" which is not a valid method name due to the ".". There is also an error caused by the class being ported from the Windows cookbook that mostly affects client skus of Windows (clients are not usually managed with Chef, though they are often knife workstations).

Also, on Win2k12 R2, the windows_server_2012_r2? method will return false and windows_server_2012? will return true due to a change in the Windows api -- see http://msdn.microsoft.com/en-us/library/windows/desktop/ms724439(v=vs.85).aspx. 

The fix addresses these issues and adds tests to correct them.