Don't print the entire declaration of the alliassee when `->toChars()` is called on an `AliasDeclaration`; just printing the name will do. This fixes #305, which otherwise tries to generate {{{ class E { void A() { alias /* recurse into E->toCBuffer() */ m; } } }}} by way of an infinite recursion (causing a segfault when the stack runs out).

module bug29;
extern(C) int printf(char*, ...);

void main()
{
    int[] arr16 = new int[4];
    {
        void[] arr = arr16;
        {
            printf("%lu\n", arr.length);
            {
                assert(arr.length == 16);
            }
        }
    }
}