[SFX] add sound positions and distance volumes

[Romuald78]

For each sfx component add several fields

• position
• near, far and max distances
• near and far volumes

In the sfx system add a service to set the listener position (link from scene and world)
According to this listener position and the sfx fields above, the system will adjust the volume according to

The volume will be 'near volume'id distance is less than near distance
The volume will be 'far volume' if distance is between max and far distances
The volume will be interpolated between near and far distancés
If distance is more than max, sfx volume is 0 (may be paused or stopped ?)

In the system, may be a 3d sound management could be done ?

Then a script is needed