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 bug50;
extern(C) int printf(char*, ...);

struct S
{
    int i;
    float f;
    long l;

    void print()
    {
        printf("%d %f %lx\n", i, f, l);
    }
}

void main()
{
    S s;
    s.print();
    s = S(1,2,3);
    s.print();

    S[] arr;
    {arr ~= s;}
    {arr[0].print();}
    {arr ~= S(1,2,3);}
    {arr[1].print();}
}