RFA: Please review the new C++ demangler patch

[Jan Reimers]

> 
> Possibility 3: make the demangler self-contained by writing a 
> mini-library
> to cover the aspects of <vector> and <string> that are used in the
> demangler, but leave it as C++.  This might not be as hard as 
> it looks.
> 
This option appears quite compeling, as presumably other portions of the C++
tool chain could then also use <vector> and <string> from the new so called
"libiberty++".