Configure machines to join specified domain for Active Directory integration

[Gentux]

As an admin in configuration section, we should be able to configure whether or not windows machine should join the domain.

[dynamiccast]

This is partially handled with hostname here: #452.

[marc-cabocel]

In order to properly join a domain, 2 steps need to be done :

• Generate unique hostname for the windows
• Join the domain with the following command : netdom join /domain:soitec.com /userd:user /passwordd:pwd

The first step can be done without rebooting the windows but not the second step. Moreover, it is not possible to configure the second one as a runOnce variable