[Gzz] Gfx Debug.hxx

[Tuomas Lukka]

I'm defining a new macro,

#define DBG(cname) if(cname) (std::cout << cname#___DBGNAME << ": ")

along with changing DBGVAR (and, appropriately, PREDBGVAR) to

#define DBGVAR(cname, name) const char *cname#___DBGNAME = name; int &cname = 
Debug::var(name)

This means that from now on, in gfx/ the correct coding policy is to 
use

        DBGVAR(dbg, "foo.events");

        ...
        DBG(dbg) << "Help!\n";