Further improvements to MessagingServerTools and the WindowsService

- I've cleand up some small things and also disabled all buttons on dooing a task.
- I added the commandline-parameters --install, --uninstall, --start and --stop to the WindowsService
- I made some changes to the setup.iss to allow also the start of the MessagingServerTools at the end of the Setup.
No further actions are required by the setup for handling a running WindowsService. As I understand InnoSetup can handle running WindowsServices and stop them and restart them after the setup is done. I've tested it and with a running WidnowsService which blocks the setup InnoSetup prompts for stopping the service and restarts it afterwards. I have commented out the option to install the WindowsService on postinstall.