Fixes #3266 - Cell timers will no longer start automagically

* Cell timers will no longer start counting down automagically
* Made cell timers use world.timeofday instead of world.time
* Separated the countdown timer and the "set timer" controls
* You can now modify the cell timer without fucking up the countdown entirely
* Absolute paths, because

![brigdoors](https://f.cloud.github.com/assets/1355638/864423/ff2c34ae-f620-11e2-8df3-1331636f0bc9.png)