WeekdayBetween : pretty output

Prettify output for weekdays between goodie. Here's the new look - 
![skitch](https://cloud.githubusercontent.com/assets/249690/4041302/fda33500-2cf3-11e4-86fc-ee2d1b86af2a.png)

thanks @chrismorast for suggesting it. 





@syst3mw0rm I know the test suite isn't yours but can you add a test for the primary_example_query while we're here? I'll merge once it's done :+1: