Support LuaJit and bug/performance fixes

• Support both PUC-Rio Lua and LuaJit
• Single integrated build that builds all dependencies including libuv, PUC-Rio Lua, LuaJit and Luaw itself in single make command
• Multipart file upload parser
• Breakup Luaw in to small independent Lua library modules
• Changes to handler definition syntax
• Remove unnecessary buffer allocations