Fix football player cards at mobile breakpoint. 

- Fix rendering issues of player cards at default mobile breakpoint.
- Adjust default avatar size

### Before
![screenshot from 2014-05-07 12 46 41](https://cloud.githubusercontent.com/assets/80089/2901927/9cb3cf24-d5dd-11e3-913e-b09b166ec24c.png)

### After
![screenshot from 2014-05-07 12 45 57](https://cloud.githubusercontent.com/assets/80089/2901928/a25f0934-d5dd-11e3-84eb-0076176cf384.png)


/cc @superfrank