Timer continued

This is a continuation of #505, updated for `bttf`. Sorry for the monster merge commit in there, apparently I don't know how to rebase :/. I'm still looking for a good alarm sound to play on completion of the timer.

![screenshot from 2014-06-01 20 32 01](https://cloud.githubusercontent.com/assets/4411471/3143224/f8501d5a-e9ed-11e3-96c2-70392eaafd7f.png)
![screenshot from 2014-06-01 20 32 53](https://cloud.githubusercontent.com/assets/4411471/3143225/f95f7308-e9ed-11e3-94bb-f119c91cd3b1.png)
![screenshot from 2014-06-01 20 33 37](https://cloud.githubusercontent.com/assets/4411471/3143226/fad91bf8-e9ed-11e3-8ba8-ccfec23b9b0a.png)
<img src="https://cloud.githubusercontent.com/assets/4411471/3143242/ab412080-e9ee-11e3-89db-bbff142e2784.PNG" width="250px" />

Not sure how I feel about the spacing in the mobile screenshot, though.

I did this to increase the accuracy. You can see what I mean if you try stopping it when the second just ticks, versus when the second is about to tick. When you start it again, it will play the rest of the second accurately. I'm not sure that would happen if I go this route. (for example, if you repeatedly click the play/pause button, you'll lose seconds) I guess a second doesn't really matter at this level of precision though...