make show categories linkable to search, adds in more button on homepage

Closes #188 , addresses part of #171 

![screen shot 2014-12-01 at 3 38 14 pm](https://cloud.githubusercontent.com/assets/1656824/5255361/1c3e89f6-7970-11e4-893d-553896dbd086.png)
![screen shot 2014-12-01 at 3 38 02 pm](https://cloud.githubusercontent.com/assets/1656824/5255362/1c4195f6-7970-11e4-85d2-02fcea586487.png)