xinetd module, windows support and CentOS/Debian package name fix

I had to update the check_mk module quite a bit for my current project.

Switched to the puppetlabs/xinetd module to avoid conflicts when multiple xinetd modules are in use. The if exists statement still failed if it was sooner than the shared module.

Added windows installer (and powershell dependency) to get the agent to run on windows. 

Package name failed on my CentOS 6 install, and logwatcher is in the same package. So created a case statement to check for RH/Debian and install the right packages.