Quickly updated the readme.txt file intended for Valve, enhancing clarity and going into greater detail.

Cobblestone Crusader, Version 3.5:

Stone Texture:

- Scaled down the entire texture for both teams
- Removed tint on Red team

Wood Texture:

- Slightly decreased contrast for both teams
- Removed original Blu wood, replaced it with slightly adjusted Red wood

Metal Texture:

- No longer metal, closer to a solid color
- Slightly fuzzy, almost unnoticable
- Removed tile overlay
- Increased redness on the Red side

Cobblestone Crusader, Version 3:

Stone Texture:

- Slightly increased artifacts and imperfections to hopefully better fit TF2's art style.
- Moved bricks around to decrease noticeable repetitions.

Wood Texture:

- Created another new wood texture from scratch for hopefully the last time.
- Stripes still exist, but are much less compact and significantly less noticeable.
- Added soft grain to both wood variants to make it look more like wood.
- Slight imperfections added to break up the texture.