LLVM full optimization

[yukoba]

This pull request is for LLVM full optimization.

I added two functions.

1. JavaCPPLLVMOptimizeModule(): This function does the standard LLVM optimization, and based on main() of llvm/tools/opt/opt.cpp.
2. JavaCPPLLVMCreateOptimizedJITCompilerForModule(): This function is similar to LLVMCreateJITCompilerForModule() but does CPU specific optimization.

I added JavaCPPLLVM prefix to avoid the conflict against LLVM-C function names.

[saudet]

I don't see any LLVMOptimizeModule() or LLVMCreateOptimizedJITCompilerForModule() functions.
How do those names conflict?

[yukoba]

Yes, LLVM does not have LLVMOptimizeModule() and LLVMCreateOptimizedJITCompilerForModule(). But if LLVM creates those functions in the future, JavaCPP has to change the name and cannot keep the upper compatibility. Therefore I added JavaCPPLLVM prefix.

[saudet]

Right, but we're not adding to the C API, so we don't need to follow its conventions. We can also make it more object-oriented. Let me propose something.

[yukoba]

Thank you. Please merge.