Add beacons to the RA spy plane and parabombs

![spybeacon](https://cloud.githubusercontent.com/assets/167819/3491696/22a0f116-059a-11e4-9b48-fbc2a826877a.png)

This also removes some redundancy by using AirstrikePower for the spy plane.

Note: Paratroopers is getting a proper rewrite, and will be its own pr.