This moves a general function from `cmpAttack` to the Entity-helper, where it seems to fit better.:
Split from D2229.
Also a- Renames `Entity.js`-helper to `PositionHelper.js` for that name seems to fit better.
- Moves to that file:
-- `EntitiesNearPoint` (from `Attacking.js`).
-- `InterpolatedLocation` (from `Attacking.js`).
-- `TestCollision` (from `Attacking.js`).
-- `PredictTimeToTarget` (from `Attack.js`).
- Adds a test for the helper and r.
- Removes the svn:executable propset.