Removed OS specific settings, this is user data and should not be define...

Hello,

today I stubbled upon a duplicate resource declaration error trying to rotate wtmp;
I was quite baffled because i had no duplicate declaration in my node definition whatsoever.

```
Error: Could not retrieve catalog from remote server: Error 400 on SERVER: Duplicate declaration: Logrotate::Rule[wtmp] is already declared in file /etc/puppet/manifests/nodes/basenode.pp at line 63; cannot redeclare on node someserver.tld.be
```

After some time I found out logrotate::base includes some OS specific defaults.
Could it perhaps be more opportune not to define OS specific settings in the logrotate::base class?

I agree with the Logrotate::Rule global setting, but defining settings (wtmp) for a specific OS should be included in a module for global purpose.

Kind regards
Fabian