MaxClients Check and test 

Update on MaxClients check using parse_vhosts function. Will also actually return vhosts values with updated regex check. 
Why prepend `apache2[:config_path]` to `error_main`? Testing on Ubuntu 12.04 gives me this as `error_main`:

```
/etc/apache2/var/log/apache2/error.log
```

This causes vhost parsing to error out.