tweak RegressionTests.sh to not build BUILD_EXTRA_COMPILERS_IF_MISSING except on Linux
tweak RegressionTests.sh to not build BUILD_EXTRA_COMPILERS_IF_MISSING except on Linux

SophistSolutions/Stroika,SophistSolutions/Stroika,SophistSolutions/Stroika,SophistSolutions/Stroika,SophistSolutions/Stroika