UI tweaks for mobile usage

- added tweet-container
- moved meta-data to the top of the tweet
- made buttons significantly larger for better usage on mobiles

NOTE: Would love to remove "conversation" and "in reply to" links!

![screen shot 2014-11-21 at 13 13 43](https://cloud.githubusercontent.com/assets/534272/5142390/e02e90b4-7181-11e4-8af6-90954bafeb64.PNG)