New library function request: calculate_distance

[evildogbot100]

Hi, I am wondering whether distance calculation can be moved to c++? As of now, even though it is widely used, most distance calculation has to be done on lua side. I am wondering can it be moved c++ where it is faster. The proposed implementation is to either put it as a function on LuaGameScript or LuaSurface, where there are 3 version of the function: between position-to-position, position-to-bounding-box, bounding-box-to-bounding-box.