Put code coverage into appledoc header

![](http://blog.millermedeiros.com/wp-content/uploads/2013/12/I-have-no-idea-what-I-am-doing.jpg)

This fetches the stats from Coveralls and shoehorns them into the appledoc header. Will probably break horribly for non-GH repos and if there's no actual coverage data there, but it's a start :)
We shouldn't calculate this at this time, cocoadocs could be generating documentation before travis finished. This is why we pull the build status in the client via JavaScript.

We will have to move this to be done in JavaScript.

The travis change was done in https://github.com/CocoaPods/cocoadocs.org/commit/c65643580e2c9bb8a6cb95db23f6fbfc95410dd4 and https://github.com/CocoaPods/cocoadocs.org/commit/de06fbe34298dbcbaa2e10ac1ca0ad2f26075f53