switched to svg badges

[ci skip]

Because they loook nicer

![screen shot 2014-11-18 at 11 34 25](https://cloud.githubusercontent.com/assets/556268/5085904/e26b2a8a-6f16-11e4-86fc-30996149ad56.png)

![screen shot 2014-11-18 at 11 34 49](https://cloud.githubusercontent.com/assets/556268/5085908/ecffc01e-6f16-11e4-962b-cde3e1871a0c.png)