Save/Load a whole scene with everything inside

I need to save all the progress, newly created GameObjects, and everything in the scene, close the game, open it again, and finally load the save scene.
Sounds really simple, but I’m making a RTS and this is the one thing that is making me become crazy.

I’ve tried PlayerPrefs, and EasySave/Load addon, but I don’t know exactly what do i have to do.

How can i do this?

The thing is that playerprefs only stores float, int, and strings. There was a guy that made a serializer which stores quite everything: See this video on youtube, and it was completly free! but it is for unity 2.x

I hope someone could bring this thing on unity 5 or make something similar, also saw this, but I don’t think it does what I need.

I really can’t believe that the hardest thing of making a game with Unity is making a save/load manager.