Major linguistics tweaks, texture fixes and edits, integration and rebalances

[Rosnok]

Alot of stuff has been changed, but mostly for the Combat Extended part of this mod.

A detailed rundown below:

Alot of description fixes and increased clarity to what they do. Also relabels to be accurate to appearance. All across the board.
And a bit of cleanup in the English language folder, remaining the ones only needed/important.

132mm rocket speed on world map has been slowed down. It was going light speed before, but now it travels slowly like a rocket now.

Flamethrower bunker weapon stats have been changed so it actually now fires a stream, instead of low fire rate fireballs it used to be before.

Renamed wall bunkers to citadel bunkers for added distinction. They also now have proper projectile offsets so they actually come out of the slits, and not from the center of the bunker.
Also added muzzle flash support for the machine gun citadel bunker and 37mm AT gun bunker.
Lastly, these citadel (formerly wall) bunkers now have limited firing arcs, to prevent shooting from behind. I might change the default firing arc to be more generous.

Now, I don't know if 81mm mortar bunkers are supposed to have a turret, but I added its turret that I found in the texture and added proper outlines and correct UI icon.

The autocannon turret bunker and twin machinegun turret bunker received a texture size tweak to be more accurate to its actual size (before it was 2x2, now it is 3x3, likewise) and a small texture edit to add the same little hatch seen on other permanent defensive structures. Projectile offsets for twin MG bunker to make it seem its firing out of two barrels. Changed its sound to use the MediumMG soundDef from Combat Extended.

Turned the seemingly unfinished twin heavy flak gun bunker structure into a complete permanent structure, complete with electricity consumption like the rest of permanent structures and functioning dual barrel projectile offsets.

All permanent structures have now a new written description snippet to let the player know it is a permanent structure, and what such designation exactly does.

Rebalanced citadel wall structure and fixed embrasure height, now similar to Combat Extended's embrasures height. Added 2 concrete cost per wall, to encourage player to utilize more concrete.

Exterior walls have been given a proper description, and fixed the blueprint atlas texture to be light blue like vanilla blueprint texture. Added 2 concrete cost per wall, to encourage player to utilize more concrete.

Added limited Vanilla Cooking Expanded integrations to the field kitchen building. It can now cook deep fried vegetables and meat, and make grilled meals.

Oh, and lastly, I made the Katyusha rocket launcher become a true artillery, now being able to shoot over mountains to strike the enemy. Almost forgot about this part.

[Rosnok]

Note: Latest versions of Combat Extended (beyond the December 15th dev snapshot on the Steam Workshop) like the release candidate released https://github.com/CombatExtended-Continued/CombatExtended/releases/tag/v1.6.7.1.0-rc1 now fixed the turret fire arc comps not respecting the toggle in the mod settings.

If you want the turret fire arcs embedded in the mod for certain turrets, then you must enable this setting to use them. Otherwise, it's all gonna be now 360 degrees without the gizmos to set firing arcs