Runtime selection library only supports std::list as a collection

[doczir]

The current implementation of the runtime selection library in it's current state only supports std::list and the intermediate selections from chains in the following operations:
select_any, select_any_where, select_many, select_many_where

This causes compilation errors when a .one() is called on a set.

[doczir]

A possible solution would be using C++11 (in case of select_any, but applicable to the others):

template<template<class...> class Container, class Value, class... Args>
inline Value select_any(const Container<Value, Args...>& ct) {
    return (ct.begin()!=ct.end())?*ct.begin():nullptr;
}

[abelhegedus]

List and set are supported, other implementations are not needed at the moment, so I put this in the Future milestone.