Add samples showing how to use LLVM modules to produce bitcode files

[junlarsen]

Based on a conversation in the JavaCPP Gitter I have put together two samples showing how to deal with LLVM Bitcode from JavaCPP. The following samples have been added:

• EmitObjectAndBitcodeFiles: A sample explaining how a user may emit both object and LLVM Bitcode files from an in-memory LLVM module. This is a pretty common task when using LLVM so I think it's a good sample to have.
• RunFunctionFromBitcode: A sample parsing an LLVM Bitcode file into an in-memory LLVM module and then running a function inside the module via the LLVM interpreter. This is a continuation of the sample from the Gitter conversation.