fixed typo
fixed make file

 - fixed wrong shared_ptr rule
fixed typo

- getLuaUpValuesIndex -> getLuaUpValueIndex
improved sample

- push function demonstration
improved samples compatibility

- “integral::defineInheritance(luaState,
&std::reference_wrapper<Object>::get)” would not be effective if the
method was inherited in the implementation of reference_wrapper;
- same rationale applies for “integral::defineInheritance(luaState,
&std::shared_ptr<Object>::get)”
Lua compatibility (5.1, 5.2 and LuaJIT)
improved samples
added rtti polymorphism sample