[#938] Add support for unique temporary folders.


Problem description
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This branch add base support for unique temporary folders.



Changes description
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Each TestLocalFilesystem will use a separate temp folder, based on OS temp folder.

There is a method to setup and teardown the temp foldres.

Also the TestLocalFilesystem class will keep a record of all instanciated temp folders so that at the end we can check that all folder were removed.


How to try and test the changes
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reviewers @alibotean 

Check that changes make sense.