Since rP9055 or so units do not make sounds anymore when walking, and so do horses.
This due to two factors, one the code in UnitAI and in VisualActor not doing his job, and two because actors do not specify event
I'm not sure but I think this will allow buildings to make ambient sounds. Since we can now set the idle tag to play sounds if the building have an idle animation it would probably play it (and since it use the same things than anims it will only be locally) refs https://trac.wildfiregames.com/ticket/1962
TODO :
Adapt sounds so they are not as loud
Adapt sounds so they fit units movement (for now they lag a bit behind)
Decide whether it's a good improvement and should be added or not. If not, we can just fix the code, and remove the walk tags in the template_unit_* files.