incorrect style prop, should be verticalAlign

[MACSkeptic]

https://github.com/rackerlabs/canon-react/blob/74bd1d4488a7878473878ab2397c590f466cb349/src/FormFieldValidationBlock.jsx#L13

causes this problem:

1) Pricing/EditDiscountPopover submitting the form shows an error for negative numbers:
     Error: Warning: Unsupported style property vertical-align. Did you mean verticalAlign?
      at failIfMessageShouldBeConsideredAnError (support/client.js:21:11)
      at Console.handleReactErrors [as error] (support/client.js:47:3)
      at Context.<anonymous> (app/racker/components/pricing/popovers/EditDiscountPopoverTest.js:157:37)