Add support for setting UUID (#667278)

Add the ability to set a new random UUID on file systems that provide
the appropriate tools to perform this action.

Update the help manual to include this new functionality.  Also add
reference links to "setting a partition label" and "changing a
partition UUID" in the "copying and pasting a partition" section.

This patch does not include setting the UUID on an NTFS file system.

Bug #667278 - Add support for setting UUID

Bug #608308 - fix documentation - Copying and Pasting a Partition