Make call_with_stack_args_and_push_lerror noexcept.
Remove unused unmember_function metafunction.
Formatting: Remove double semicolon.
No camel case for detail::push_function().
Sort includes.

1.1. <apollo/*>
1.2. <apollo/detail/*>
2.   External libraries
3.   Standard Library

Inside these groups alphabetically.
detail::make_class_info(): Avoid warning.
Sort names in CMakeLists alphabetically.
Add & test member function from_stack.

Also add missing test for actually calling a member function.
More member function tests.
Add push_function_static (& helper macro).

This allows to bind functions to Lua with zero overhead compared to a manually
written wrapper function. However, functions pushed that way cannot be retrieved
using from_stack.