Fix test_progress_exit integration test.
Fix test_progress_exit integration test.

- Small errors in progress are expected due to extrapolation.
- Allow for a window of 10% error at most.
- Increase the big-o used for this test so that there actually are
  progress values in the trace that are not 0 or 1.
- Only look for negative progress in the spin region where
  the frequency of reporting from the application is regular
  and independent of the performance of the processor.
- Improve calculation of epsilon to work for negative numbers.
- Fixes #94 from github issues.

Change-Id: Idbf99cdeca02c463d0a7e63e3fb5cc8ad2c318d0
Signed-off-by: Christopher M. Cantalupo <9cf3ecca60a3dd7112ab0e7250bedb8a752e3958@intel.com>

cmcantalupo/geopm,geopm/geopm,geopm/geopm,geopm/geopm,cmcantalupo/geopm,geopm/geopm,cmcantalupo/geopm,geopm/geopm,cmcantalupo/geopm,cmcantalupo/geopm