Add a config switch to ship user-specified files/directories e.g `/var/log`

[mfrw]

In order to aid debugging a breaking-test case and understand what exactly happened while the run of a test, it would be helpful if we could zip the contents of: /var/log, for example, and ship them as well.

[SRIKKANTH]

It can be handled within testcase doesn't have to be a feature in the framework.

[squirrelsc]

Thank you for the feedback. There is a task to create system snapshot when a test case failed, and it can be called on anytime in a test case.