Added the capability for the test driver to split the sys.stderr/sys.stdout into
drwxr-xr-x - clang
drwxr-xr-x - compiler-rt
drwxr-xr-x - debuginfo-tests
drwxr-xr-x - libcxx
drwxr-xr-x - lldb
drwxr-xr-x - llvm