GMR-193: Add missing utlity include, needed for std::forward
apply Gaudi Merge Request 193: gaudi/Gaudi!193 (merged)
Add missing utility include, needed for std::forward
See build errors in https://lhcb-archive.cern.ch/artifacts/nightly/lhcb-gaudi-head/1180/summaries.x86_64-slc6-gcc49-opt/Stripping/build_log.html