Initial Commit
Added FFI for Lua

Nearly full support for standard API
Partial support for debug API
Minimal support for aux API
Added simple crate file
Corrected function definitions

Also added missing constants, and declarations for lua_load,
lua_absindex, lua_arith, lua_atpanic, and lua_iscfunction
Added basic safe wrapper

Implemented simple stack operations, pushing and pulling values between
Lua and Rust
Added appropriate license