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).

#!/bin/sh

g++ llvm-ext.cpp -c `llvm-config --cxxflags`
g++ llvm-opt.cpp -c `llvm-config --cxxflags`
g++ llvm-typemonitor.cpp -c `llvm-config --cxxflags`

rm -f libllvm-c-ext.a
ar rc libllvm-c-ext.a llvm-ext.o llvm-opt.o llvm-typemonitor.o
ranlib libllvm-c-ext.a