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 tangotests.gc1;

void main()
{
    int[] arr;

    for (int i=0; i<100; ++i)
    {
        arr ~= new int[1000];
    }

    printf("arr.length = %u\n", arr.length);
}

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