Added star collapse

Stars now collapse on death into either a black hole, neutron star, or pulsar

![2014-09-21_20 21 05](https://cloud.githubusercontent.com/assets/777873/4350526/1abf6cde-41ef-11e4-816e-7f656be1ee6c.png)

![2014-09-21_20 22 00](https://cloud.githubusercontent.com/assets/777873/4350527/1eecb2a8-41ef-11e4-9bb1-3fae854dbd64.png)