Use consistent temporary directories for test_cookbook_burp.py.
Use consistent temporary directories for test_cookbook_burp.py.

The temporary burp files were going into a 'tmp/' subdirectory from where the
tests were run, but that directory might not exist.  Use TMPDIR instead.

meteokid/python-rpn,meteokid/python-rpn,meteokid/python-rpn,meteokid/python-rpn