New feature; Snapshot in a multi node profile.

Hi all. We have added a feature to make it a bit easier to take snapshots within a multi node profile. This feature is accessed from the per-node context menu; click and you will see a new option in the menu, "Snapshot". 

If you select that, you will be shown the following modal:

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The first check box asks if you want to update your profile after the snapshot has completed, by changing all of the nodes that are running the same image, to use the new image. In general you want to leave this box checked, unless you want to edit the source code yourself. 

If you have several nodes in your profile, all running different images, and you want to take snapshots of, each one you have to do each one individually via the context menu for each node. 

The second checkbox is to address the problem that many users have with accounts and groups getting deleted when you take a snapshot. This typically happens when you install a software package that adds a user and/or group. Those get deleted by default, but if you check the box above, they will be retained permanently (you don't need to check the box the next time you take a snapshot). Note that your user account is always deleted no matter what, to encourage you not to build in dependencies on specific user directories. :-)

The reason this is not the default, is because in general you do not want to take the chance that an account with a bad password will be propagated forward to every time you create a new image.

As always, comments welcome we always want to hear what people think.