What I expected to happen was...:
When I write stuff on a sign there will not be formatting text on it

What actually happened was...:
The sign places normally on 1.7.10 but when you switch to the snapshot the formatting appears

Steps to Reproduce:
1. Open 1.7.10
2. Open a world
3. Place a sign with whatever text
4. Restart minecraft in 14w29a
5. Open the world
6. There will be hidden formatting on the sign

On the screenshot I show some signs affected by the bug. I made the signs without the " or null on them. After I updated they were like this.