Fix compilation with ROOT 6.12
- add use of TBB (now required by ROOT)
- replace
string == 0comparisons withstring.empty()
Note that string == 0 used to compile because it used operator==(TString, const char*).
Edited by Marco Clemencic
string == 0 comparisons with string.empty()
Note that string == 0 used to compile because it used operator==(TString, const char*).