Bug fix argument passing to ltFit.py
Increase integral accuracy by a factor of 100
Do acceptance fit with new selection

1. PIDK < 0  - Dsπ
   PIDK > 10 - DsK
2. BDTG > 0.5
3. Trigger (same as before)
Fit with RooFit.Offset(True)

Enabling this option subtracts the initial value from the likelihood.
This way large likelihood values are avoided.  As a side-effect, the
minimum occurs at -ve values of the likelihood.

See Manuel's email for details:

  (notmuch-show "id:20130430004557.5ddf0e98@nikhef.nl")
Add time stamp to acceptance ratio plot file name
Bug fix: default argument for no cuts
Add raw ratio plot to investigate 6.5 ps kink

Conclusion: statistical fluctuation