[std] Fix PDF title and subject. (#4208)

Do not claim the document is an "International Standard";
it is just a Working Draft.

Author: jensmaurer

source/std.tex

@@ -30,8 +30,8 @@
 \usepackage[T1]{fontenc}
 \usepackage[pdftex, final]{graphicx}
 \usepackage[pdftex,
-            pdftitle={C++ International Standard},
-            pdfsubject={C++ International Standard},
+            pdftitle={C++ Working Draft},
+            pdfsubject={ISO/IEC JTC1 SC22 WG21, C++},
             pdfcreator={Richard Smith},
             bookmarks=true,
             bookmarksnumbered=true,