fix(style): remove end padding from text inputs

Fixes #1843 

![screen shot 2014-11-14 at 10 45 18 am](https://cloud.githubusercontent.com/assets/3323249/5048513/4edbaaba-6bec-11e4-95d8-48b7a855162b.png)


Also changed mixins to camel case because they're more legible that way (IMHO)