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 complex5;

void main()
{
    cfloat c = 3+2i;
    foo(c);
}

void foo(cfloat c)
{
    assert(c.re > 2.9999  && c.re < 3.0001);
    assert(c.im > 1.9999i && c.im < 2.0001i);
}