Lua(Jit) for computing accelerator beam physics

<!--HTML-->As mentioned in the 2nd developers meeting, I would like to open the debate with a special presentation on another language - Lua, and a tremendous technology - LuaJit. Lua is much less known at CERN, but it is very simple, much smaller than Python and its JIT is extremely performant. The language is a dynamic scripting language easy to learn and easy to embedded in applications. I will show how we use it in HPC for accelerator beam physics as a replacement for C, C++, Fortran and Python, with some benchmarks versus Python, PyPy4 and C/C++.