Fixed misalignment with sent/receive tooltip

Before:
![screen shot 2014-10-27 at 1 21 11 pm](https://cloud.githubusercontent.com/assets/5728307/4799060/3b2e32ac-5e19-11e4-8f0e-f7a339a0bec5.png)

This PR aligns the height (there is a little arrow on the `view all balances`) and also fixes the centering issue on both Firefox and Safari.

Fictional: This PR also solves a big chunk of the US debt.

https://github.com/stellar/stellar-client/issues/990