Switch test/ttSemiLepSignalSelMVATrainTreeSaver_cfg.py to unscheduled an...

...d modify to show effect with the new PAT defaults (cleaning added here).

This fixes the IB test crash reported in
https://cmssdt.cern.ch/SDT/cgi-bin/buildlogs/slc5_amd64_gcc481/CMSSW_7_0_X_2013-11-22-0200/unitTestLogs/TopQuarkAnalysis/TopEventSelection