Feature/number formatting

A couple of formatting tasks:

* Make the threshold for displaying numbers as `12.3k` 10,000, so 1234 will appear as `1,234`.
* Render percentages to 1dp by default.

Also... 
![](http://www.livememe.com/7l3mo8x.jpg)

Formatters no longer live on the view, and are now (with the exception of `formatPeriod`, but that's coming next, and this PR is big enough already) all in formatters.js.

![](http://lathewerks.com/images/Misc/GIF%20BossHedgeTrimmer.gif)