Working trampoline POC

build with:
clang -O0 -g -S -emit-llvm runtime.c
llvm-as-3.0 -o runtime.bc runtime.s && llvm-as-3.0 trampoline.ll && llvm-ld-3.0 -native trampoline.bc runtime.bc && ./a.out
convert to closure factory
get rid of list stuff for the moment, extract method to create closure node