Option to force units to touch their move goal

[marcushutchings]

It may be desirable for games to have situations where a group of units must touch their given move goals. At the moment, there is logic where the engine decides the unit has got close enough if the unit touches another unit that is standing on its move goal. This is to reduce drawn battle lines being pushed too far ahead and it also reduces units stringing out into a single line as they follow multiple move orders around a map. Normally, this is preferred, but there may be times when the games really wants each unit to touch their move goals fro themselves. Ideally, this should be something that can be handled on the move command itself.