SortHistos.C Calibration is now working for signle or multiple souerces!
Just a few changes to accomplish that.
- Changed where output files are closed.
- Swapped some . and ->'s.

Only remianing problems before this whole multi-source calibration issue is fixed:

- Option PLOT_CALIB_SUMMARY causes the code to hang at the first plot.
- General switching between canvas's for plotting is cumbersome and weird, need to fix.