Format-Utils: switch to demangled type names

TODO: might break some unit-tests...

Explanation: our wrapper around boost::format has special
built-in support for custom operator string(). Any type,
which is neiter standard, or printable through such a
custom string conversion, is represented as a type-string.
For this fallback case, we now use our recently added
demangling call (which actually relies on a rather obscure
but standard compiler API)

src/lib/format-util.hpp

@@ -48,6 +48,11 @@
 #include <boost/utility/enable_if.hpp>
 
 
+namespace lib {
+namespace test{ // see test-helper.cpp
+    std::string demangleCxx (lib::Literal rawName);
+}}
+
 
 namespace util {
   
@@ -107,7 +112,7 @@ namespace util {
   inline string
   tyStr (const TY* =0)
   {
-    return string("«")+typeid(TY).name()+"»";
+    return "«"+ lib::test::demangleCxx (typeid(TY).name())+"»";
   }
   
   template<typename TY>