Game crashing after some times

[Exeloo]

When running a game, the game will crash after some minutes

[MartinFillon]

Might be linked to the systems running, might be fixed with this code

void run_systems(const emscripten::val &ctx)
        {
            emscripten::val registry = ctx["libs"].call<emscripten::val>("getComponentSystem")["registry"];
            std::vector<emscripten::val> systems_copy = _systems;
            for (emscripten::val &system : systems_copy)
                system(registry, ctx);
        }

This is not the best code but we can take a look to change it later on.

[Exeloo]

Need to check if it's still here after #156