Tells vboxwrapper to copy its cmdline args to shared/cmdline.
This lets you use the cmdline mechanism as a way to pass
info to the VM that would otherwise have to go in a file.
Note: the cmdline can be fairly large.
It shares the wu.xml_doc field with file descriptions.
This field can be up to 64KB (MySQL blob size)
Basically the VM periodically 'touches' the file to let the wrapper know that it is still alive. If the wrapper does not detect a change to the mod time of the file at the specified interval it assumes the worst and aborts the job.
Requested by CMS.
David Anderson