Backward compatible changes required for Gaudi/master
- fix for LCG 95 (ROOT >= 6.14 dependency on BLAS)
- fixes for gaudi/Gaudi!534 (merged)
- fixes for gaudi/Gaudi!514 (merged) (LHCBPS-1831)
- fixes for gcc8
See LHCBPS-1827
Edited by Marco Clemencic
See LHCBPS-1827