capture also stderr from $CXX --version use cmake to keep only the first line; fixes Open64 detection
capture also stderr from $CXX --version use cmake to keep only the first line; fixes Open64 detection

chr-engwer/Vc,VcDevel/Vc,VcDevel/Vc,VcDevel/Vc,chr-engwer/Vc,VcDevel/Vc,chr-engwer/Vc