Document did not compile under Windows

because `\lstinputlisting` was not able to find files without extension (e.g. `configuration/Webservers/Apache/default-ssl`). Workaround is to add a dot at the end of the file name. This patch modifies the `\configfile` command to detect the platform via the `ifplatform` package and adds a dot at the end of all file names on Windows systems.