fix tracker.xml

tested runTheMatrix.py --what upgrade  -l 4500 
with 100 events, before (red) and after (black) on the #hit/eta 
![fix_tracker](https://f.cloud.github.com/assets/5131720/2046694/d4d48526-8a09-11e3-98b5-06a8725174cd.gif)

Fix was discussed in the PR 2232

hope I didn't screw up this PR as the status is " Error checking merge status" but don't worry it said ;-)