[FIX] Trust: Remove duplicate reserve warning (RT-2767)

When trying to connect a gateway while there are insufficient reserve
funds, the yellow warning bar appeared twice: Once above the content,
once on the right of the currencies menu.

@rippletravis

- Before:
![before](https://cloud.githubusercontent.com/assets/6348321/5217244/207399e2-763e-11e4-93c2-53e1564218fc.jpg)

- After:
![after](https://cloud.githubusercontent.com/assets/6348321/5217246/24eebd44-763e-11e4-93e6-01762bd69ed0.jpg)