Support for CIL bytecode in ATS-parse-emit

This allows atsparemit tool to emit CIL bytecode (in textual syntax), and the resulting files can be assembled into binaries which run on Mono (under Linux) and on .NET (under Windows).

It's a bit raw as it is, though. For instance, parametric polymorphism is unsupported, multiple translation units are unsupported. Some examle programs (in TEST subdirectory) do work, however.