Count the number of selected evenst in fStatus
Count the number of selected evenst in fStatus

To provide an example for the fix/change for ROOT-748 just committed.

kirbyherm/root-r-tools,tc3t/qoot,kirbyherm/root-r-tools,tc3t/qoot,tc3t/qoot,tc3t/qoot,kirbyherm/root-r-tools,kirbyherm/root-r-tools,kirbyherm/root-r-tools,tc3t/qoot,tc3t/qoot,kirbyherm/root-r-tools,kirbyherm/root-r-tools,tc3t/qoot,tc3t/qoot,tc3t/qoot,tc3t/qoot