Weeks View

Sets the home page to default to 'this week' of posts.
Refactors the way of getting start of and end of week from moment.js

![screen shot 2014-08-11 at 6 16 40 pm](https://cloud.githubusercontent.com/assets/3967825/3884837/28c72c8a-21b6-11e4-8bea-7f7797394fe5.png)

This is my first stab at trying to do a weekly view as opposed to monthly (we could probably combine them and refactor the pagination logic!)