@facingDirection of roadSideLights is missing in the tree
## Background
`@facingDirection` of `roadSideLight` is in the schema but not in XML tree.
## Solution
Modeling should be fixed.
Documentation: "indicates the orientation of the lights as seen by road user". We distinguish two options: either the light is standing behind the crossed rails facing "towardsRail" or the light is standing before the crossed rails facing "awayFromRail".
issue