Action for solder edges of nearest terrains.

[Download the test level](https://drive.google.com/file/d/0B4G7HDT9STV-T0tlZTQwcEstSUk/edit?usp=sharing).

![image](https://f.cloud.github.com/assets/311074/2001586/2d541a5e-85b9-11e3-8980-0bc9a087b05c.png)
![image](https://f.cloud.github.com/assets/311074/2001590/3befb2da-85b9-11e3-89c6-1e9a8386d583.png)
![image](https://f.cloud.github.com/assets/311074/2001591/3f1e5ff6-85b9-11e3-9edc-8f033ac25975.png)