WiP demoreel environement part.2

Update of my project! In this update, i setting:
- LOD, lightmap density for render and optimisation
- Make a new texture in designer for the props and create my first trimsheet (but is not here again)
- I little modify the ambiant lighting
- Modeling more props
- And, i modify my landscape for one only (the rock) and create a modular landscape with heightmap (wherever there is sand)

Now to follow for (I hope) the final!