Fix Seraphim sniper's barrel not aiming with LOD1 model

[lL1l1]

Description of the proposed changes

• Renames the vertex group/bone responsible for the barrel vertices from lod1_Barrel to Barrel

Testing done on the proposed changes

The barrel can be seen rotating when zoomed out:

Freecam can help hide the strategic icon if it obscures your view.

Checklist

- [ ] Changes are annotated, including comments where useful

• Changes are documented in the changelog for the next game version

[lL1l1]

I don't know how to verify all the other models or if there are any other known similar issues, since this was quite a human mistake that is likely to be repeated somewhere.

Also not sure where to document this behavior of turrets and LOD models.

[Garanas]

Delivers as promised. I also noticed this, but I had no idea how to fix it.

With regards to documentation, maybe this should be on the wiki. For example:

• https://wiki.faforever.com/en/Development/Modding/Creating-models

[lL1l1]

I added a note about LoDs on that wiki page.