convert L2 bin histo to root histo

Compile this stand alone code 

 $STAR/StRoot/StTriggerUtilities/L2Emulator/macros/binH2rootH.c 

It needs  L2Histo.cxx  L2Histo.h  from

 $STAR/StRoot/StTriggerUtilities/L2Emulator/L2algoUtil/

and CERN root .

It does not need STAR root4star.