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).

#ifndef LDC_GEN_AA_H
#define LDC_GEN_AA_H

DValue* DtoAAIndex(Loc& loc, Type* type, DValue* aa, DValue* key, bool lvalue);
DValue* DtoAAIn(Loc& loc, Type* type, DValue* aa, DValue* key);
void DtoAARemove(Loc& loc, DValue* aa, DValue* key);

#endif // LDC_GEN_AA_H